The aspect of the city’s zoning plan that perhaps most strongly signals a break with the past would strike the rules that gave birth to the Combat Zone in the neighborhood. It would largely be a symbolic move, as the heyday of the notorious den of sleaze — once home to strip clubs, X-rated theaters, peep shows, and adult bookstores in the downtown core of Boston — is decades in the past.

Still, for those who advocate for Chinatown, removing a slice of the zoning that for years allowed for Boston’s only adult entertainment district in their neighborhood matters. It’s a modicum of recompense for a time when city authorities largely ignored the wants and needs of a place that has for generations offered a beachhead for immigrants.

“Chinatown suffered decades of increased crime and negative impacts on the community,” said Lydia Lowe, executive director of Chinatown Community Land Trust. “That issue is very important.”

The rezoning discussion — a comment period for the city’s proposed changes ends in mid-January — comes amid a time of transition for Chinatown, one of Boston’s smallest neighborhoods, an ethnic enclave with a rich history in the city’s urban core. Talk to seemingly anyone in Chinatown and they’ll say that displacement is their largest concern. And demographic data back up the notion that the effects of years-long gentrification continue to alter the fabric of the neighborhood.

The city’s planning department this fall released a draft of new zoning regulations and design guidelines that “seek to promote affordable housing, emphasize the significance of small businesses and cultural spaces, and highlight Chinatown’s unique character,” Brittany Comak, a department spokesperson, said in an email.

The next public meeting, focused on property owners, will be held in January, with final recommendations to come later, Comak said.

The proposal looks to better protect the neighborhood’s historic row houses — symbols of Chinatown’s working class, which now faces displacement — by capping how tall developments can be in part of the district. Residents have fought to preserve the affordability and character of those structures, saying they are integral to the area’s cultural fabric, one of the last untouched pockets of a neighborhood roiled by development.

Under the plan, the maximum height of projects would be 45 feet, down from the current 80 feet. (Chinatown’s row houses tend to be three to four stories in height.) Other restrictions, according to the city, would help ensure new buildings “would be of similar size and scale to the existing row houses” in a certain subdistrict of Chinatown.

“We find that to be a positive change,” said Müge Ündemir, director of real estate for Asian Community Development Corporation, of the city’s zoning approach to the row houses.

Other parts of the rezoning initiative are being met with questions or outright skepticism.

For instance, an affordable housing overlay district would allow developers in parts of Chinatown to build structures up to 350 feet tall, if they meet two thresholds: 60 percent of the gross floor area must be devoted to residential uses, and 60 percent of the residential units must be income-restricted and meet an affordability standard. While advocates support the idea of more affordable housing in Chinatown, 35 stories, they argue, is way too high for the neighborhood.

Karen Chen, executive director of the Chinese Progressive Association, worries that such towering buildings could exacerbate quality-of-life issues in a neighborhood where some blocks are already cast in shadow and wind tunnels are a reality thanks to past development.

“Chinatown is so small and congested already,” said Chen. “Up to 35 stories is just ridiculous.”

Through a spokesperson, the city’s planning department said the overlay “reflects heights of recent projects in the area, how other areas of downtown are being rezoned to increase allowable building height, and acknowledges the clear community priority to deliver affordable housing in Chinatown in an area of limited sites for development.”

Others are critical of the income ceiling for who would qualify for the affordable housing in such projects. Under the city’s plan, households making up to the area median income would qualify. For a one-person household, the cap would be about $114,000.

Advocates want the cap to be much lower, say 60 percent of area median income, which would be about $68,000 for a one-person household. That would more directly help the neighborhood’s working class and working poor, they argue.

“The affordability standard, it needs to match where the neighborhood is at,” said Chen, who also worries that a proposed “transition zone” would contribute to the further encroachment into Chinatown of downtown’s luxury residential towers.

Angie Liou, executive director of the Asian Community Development Corporation, concurs, saying the general idea of incentivizing more affordable housing in the neighborhood is a good one.

“The devil’s really in the details,” she said.

Officially, more than 4,200 residents live within about one-fifth of a square mile that makes up Chinatown. (Advocates have long challenged the population estimate there as severely undercounted.)

According to city figures, about 64 percent of the neighborhood’s population identifies as Asian or Pacific Islander. Half the population is foreign-born, with just under half of all Chinatown residents speaking Mandarin or Cantonese at home. There was a time when those numbers were much higher. An old master plan for the neighborhood estimated that in 1990, 91 percent of residents were Chinese.

Chinatown’s history is one of political marginalization. The Combat Zone, which is now occupied by luxury apartments and trendy restaurants, is a high–profile example of the city treating the neighborhood as an afterthought. Two strip clubs on LaGrange Street still stand in the city’s “adult entertainment district” as a reminder of what once was. They would remain part of an adult entertainment district under the proposed zoning changes, as they are located just outside of what the city considers to be Chinatown.

There is a history of development profoundly changing the neighborhood, which has never produced a Boston city councilor. Construction of the Central Artery and the Massachusetts Turnpike took sizable bites out of Chinatown decades ago, and the steady expansion of Tufts Medical Center also ate away at blocks.

Amid current gentrification and displacement challenges, many first-generation immigrants and working-class Chinese Americans still look to Chinatown for their day-to-day needs, as they have for more than a century. A plaque at Ping On Alley memorializes the city’s first Chinese immigrants, who pitched their tents there starting in 1875.

Advocates say new zoning alone won’t stop gentrification, but some hope it could have a “calming effect” on the neighborhood. Enforcement of the zoning rules also matters. Liou, of the Asian Community Development Corporation, said the city has historically given out variances to Chinatown projects on a regular basis, which has had a cumulative effect of largely rendering the existing zoning moot.

“If it’s on the books and no one follows it,” said Liou, “It’s pointless.”

Danny McDonald can be reached at daniel.mcdonald@globe.com. Follow him @Danny__McDonald.