Depending on your environment, they may not matter. Tesla cut them to save costs, not because they are offering a better alternative. As usual they didn't offer one.
I went through this with the radar removal of the Y after I ordered it and before it was delivered. If I had known what a cluster truck that was going to be, I'd have cancelled my order and sat it out for a year before the SW got to where it wasn't terrible on that car. My S had radar and then it was disabled in an update. I can categorically tell you that the car was better with radar than without with respect to Phantom braking as well as functionality.
Reducing of the top speed from 90 to 85 for AP tells you that even Tesla doesn't think a pure TV solution works as well as when radar was part of the stack. The reduction was not trivial as there is a highway I am where the speed limit is 85 mph. The speedo reads a little low, and traffic generally runs faster than posted. So I can't use AP on that stretch of road now without becoming a rolling roadblock.
So once again Tesla is downgrading our cars to save a few dollars and giving us a crappier solution in return. Anecdotally, TV generally (for AP) works better on my 3 than my Y. Don't know why just my observation. Maybe with HW4 it will be better. I've learned to not hold my breath for anything Tesla promises. Assume whatever they deliver, it isn't going to get any better. That is a safe assumption and sets your expectations for less disappointment. My Y performed so badly on TV only I ultimately sold it. I don't know if Mullermn would think the radar removal was trivial but after Tesla burned me with that fiasco, I learned my lesson big time. Hence the reason I wasn't going to buy a car without USS until Tesla has a viable option that works for me. The current TV parking aid doesn't even work as remotely well as USS.
I posted somewhere else here that there was what appeared to be a MIC (made in China) 3 driving around the Bay Area for probably testing with what looked to be parking sensors buttons in the bumper. What happens to the 3 often happen to the Y and vice versa. So the speculation was they might be bringing them back. If they do, highly unlikely Tesla will retrofit for you. Again no proof they are doing that but... Here is the vid for reference. Who knows, they may be backtracking on the removal like they did with the yoke on the Y/S.
I would really encourage OP to go drive a 3/Y with the TV being used for parking assist and make up his own mind. Hopefully there is a demo car nearby and he can see. Enjoy whatever you buy and go in with your eyes wide open. Don't assume any future functionality or remotely believe the timeline for it until you see it with your own eyes.
