This happened a few years ago, right after Adams took office.
He launched a plan to increase beds in psychiatric hospitals and increase availability of mental health workers after receiving backlash from the bench removals and subway evacuations/arrests of unhoused individuals.
It's also to help prevent panhandling, vagrancy, public defecation, harassment, theft, and violence. 23rd St. stank of human reek before the pandemic, so removing enticements for them to sleep in the station was much needed.
People will sleep when they have to sleep. And if they have a choice between outside or inside on a cold night, they will choose in. These people don’t disappear when you make their lives even harder. They have to adapt to further misery. This isn’t a solution. It isn’t even a solution to the problems you listed. Ride the train early morning or late night? You will see a bunch of homeless people trying warm or get some sleep.
I once read somewhere that people with lodgings don't sleep and/or shit in public places! Can you believe that?! Pure delusional nonsense, I'd say, made Lord of The Rings feel like an account of historical facts.
Unfortunately there are some who do. Still absolutely use a shelter/housing first model, and give money to those struggling (most homeless people are couch surfing or living out of their cars and have jobs and just need a little boost to get back on their feet) because it helps the vast majority.
For some reason through, the same people that advocate for the programs I listed above refuse to accept that there are some people they won't work for. The ones who are too mentally ill or violent or otherwise too antisocial.
The homeless aren't a monolith, and often people are talking past each other because they are each picturing people from opposite ends of the spectrum who have essentially nothing in common except their housing situation. The people installing spikes and removing benches are responding to the second group, and then face backlash as if they were responding to the first.
People don't get it. They expect everybody else to accept the burden of this because they don't have to do shit about it. I wish everyone could experience what it's like to have a small business that would be devastated by the homeless if you didn't work hard to get them the fuck out of where they don't belong. It's not my fault, my responsibility nor should it be on my limited wallet that the government can't fix homelessness. I have to kick out homeless every day and anyone else that actually lives in a position where their presence affects their ability to live and stay afloat would do it too. Let them sleep in your house or in your front yard and see how much you all like it and stand for it when they start doing drugs, having sex in the open, shitting everywhere, leaving trash everywhere. See if your friends and family want to come over ever again. Oh poor homeless guy, let me buy him some McDonalds.. I'm the dude who has to clean up all the trash he left.