looks like rendering adblockers extensions obsolete with manifest-v3 was not enough so now they try to implement DRM into the browser giving the ability to any website to refuse traffic to you if you don't run a complaint browser ( cough...firefox )
here is an article in hacker news since i'm sure they can explain this to you better than i.
and also some github docs
On iOS, there's no browser extensions (for e.g. ad blocking), no alternative browsers, and no FOSS apps of any kind. That platform is extremely hostile to the ideals of computing freedom.
Like I said, it's a better (for privacy) alternative to stock Android when you need a fully functional operating system. If you can stand to lose the oppressive Google functionality, you can go degoogled Android or preferably Linux (if you don't care about battery life or app availability).