States should unilaterally upzone cities

I've had this idea for a while and I want to know what other YIMBYs think of it. Why not focus specifically on massively upzoning existing cities via state legislatures? Let's say, as first priority?

I'm using my home state of CT as a model btw. Our cities are horribly NIMBY about new housing despite being, y'know, cities.

We have a handful of cities with dense downtowns centered on rail lines. Some have active passenger rail (Hartford, New Haven, Stamford, Bridgeport, etc) while some have rail lines, connected to the rest of the state rail network, which are owned by the state but currently only used for freight (Middletown, Willimantic, Norwich, New Britain). Here is a map of state rail line ROWs to help you understand.

Why doesn't the state legislature just pass a bill massively upzoning these cities that are connected by rail? I don't know about other states, but at least in Connecticut, they already have the authority to do that. I'm not talking about minor changes, I'm talking abolishing height maximums, parking minimums, upzoning every neighborhood in these cities to allow the maximum amount of housing that is feasible engineering-wise. It would probably be an easier sell as a bill too- the infamously NIMBY Connecticut suburbs would be less likely to protest, because in their view density should only exist in cities, and everything outside of downtown Hartford should be a single-family house. The cities already have much of the important infrastructure in place, such as bus lines and consistent train service.

Like yeah, forcing the surrounding suburbs to allow greater density also needs to happen, but I am baffled as to why our local YIMBYs are allergic to this sort of cities-first approach. I asked the director at DesegregateCT (basically the Connecticut YIMBY organization) about this exact idea, and his response was "We don't think housing is a burden to be forced upon cities, it should be built everywhere" Which I generally agree with, but Connecticut has such great bones for a mass transit network and has been consistently investing in regional rail for nearly two decades, with more upgrades underway right now. If there's any place where enforcing greater housing density upon cities pay dividends, it's in CT.

I hope the idea of my post was clear. I support upzoning everywhere, but I think we should be specifically hellbent on forcing cities to allow WAY more housing. Our cities in Connecticut ABSOLUTELY can build significantly more than they have been- but city govs insist on drowning everything in process, zoning, "inclusivity" ordinances and nonsense like that.

EDIT: Just to broaden my example: Why not have CA legislature force specifically LA and SF to allow denser housing? As in, directly, unilaterally, upzoning their city? And this goes for any other legislature in the country too.