I agree. It's insanely user-hostile that the "never auto-play" setting in Safari (for example) doesn't work and hasn't worked for years. To be honest, I have no recollection of it ever working reliably.
Although it is an arms race and obnoxious web pages can have javascript/webassembly video players that render into a canvas, etc., I still blame Apple for not sorting this out, and even backtracking on click/tap-to-play.
IIRC, at some point Apple did roll out default click/tap-to-play on iPhones, and there was a huge outcry from web developers (probably including Google/youtube) that it broke their sites. I expect the real complaint was that it interfered with pushing unwanted video advertisements.
The fact that we need a "stop the madness" app for Safari is proof of Safari's insanity.
If Stopthemadness actually works reliably, it is also an existence proof that blocking video autoplay is possible, and that Apple is simply not fixing the "never auto-play" setting in Safari.
Perhaps Apple and Mozilla should just remove the "never auto-play" settings in Safari and Firefox and say that they are doing so in order to empower web sites and adtech companies (including Google/youtube, who pays them a lot of money) to force you to view unwanted video advertisements.