Except that any housing, market-rate or not, does empirically help with affordability:

But what happens to rents after new homes are built? Studies show that adding new housing supply slows rent growth—both nearby and regionally—by reducing competition among tenants for each available home and thereby lowering displacement pressures. This finding from the four jurisdictions examined supports the argument that updating zoning to allow more housing can improve affordability.

In all four places studied, the vast majority of new housing has been market rate, meaning rents are based on factors such as demand and prevailing construction and operating costs. Most rental homes do not receive government subsidies, though when available, subsidies allow rents to be set lower for households that earn only a certain portion of the area median income.

Policymakers have debated whether allowing more market-rate—meaning unsubsidized—housing improves overall affordability in a market. The evidence indicates that adding more housing of any kind helps slow rent growth. And the Pew analysis of these four places is consistent with that finding. (See Table 1.)

https://www.pewtrusts.org/en/research-and-analysis/articles/2023/04/17/more-flexible-zoning-helps-contain-rising-rents

We study the local effects of new market-rate housing in low-income areas using microdata on large apartment buildings, rents, and migration. New buildings decrease rents in nearby units by about 6% relative to units slightly farther away or near sites developed later, and they increase in-migration from low-income areas. We show that new buildings absorb many high-income households and increase the local housing stock substantially. If buildings improve nearby amenities, the effect is not large enough to increase rents. Amenity improvements could be limited because most buildings go into already-changing neighborhoods or buildings could create disamenities such as congestion.

https://direct.mit.edu/rest/article-abstract/105/2/359/100977/Local-Effects-of-Large-New-Apartment-Buildings-in?redirectedFrom=fulltext