MV3 doesn’t make adblockers impossible, only less effective. It’s important to note that MV3 has changed a fair bit since the initial controversy and isn’t quite as limiting as it used to be. The fact that adblockers will lose some functionality at all is still a dealbreaker for me and many others which I thankfully won’t have to deal with as a Firefox user, but it isn’t going to kill adblockers on Chrome and most users will probably just install an MV3-compatible adblocker and move on with their day.
uBlock Origin’s developers don’t seem to want to make a proper MV3 port, which is fair because they’d probably have to rewrite most of the extension, but they did create the far more minimal uBlock Orgin Lite, which a lot of people have taken to be an attempt at porting uBlock Origin to MV3. It isn’t that. On top of MV3’s limitations, it also makes the decision to work within these self-imposed restrictions:
No broad host permissions at install time – extended permissions are granted explicitly by the user on a per-site basis.
Entirely declarative for reliability and CPU/memory efficiency.
These aren’t MV3 limitations, just a thing Gorhill decided to do. See the FAQ. You can get much closer to uBlock Origin within MV3’s constraints than uBlock Origin Lite does. Right now, the best option appears to be AdGuard, which has been making a true best-effort attempt at porting their adblocker to MV3 pretty much since the announcement.