You don't want to interact with me? Fine. Then why should I still see your posts? Yes, some crazy people will go to lengths to see it anyway, but most don't and will take the hint, shrug, and go away.
If you're blocked by prolific reply guys in your circle, you regularly have to not just scroll past their censored replies at the top of the reply section, but you see other people's replies to them which compels you to switch accounts to see what dumb thing they said this time. And now you can simply reply to them on your other account.
Twitter ossified their feature set a long time ago, which is not surprising because "stick with what made us big" is a reasonable course of action. In that sense great diversity and more experimentation in different approached with Threads, BlueSky, and Mastodon is generally a good thing (even though I don't really use any of them, mostly out of laziness).
Feel free to steel man and tell me why you think it's useful. I think the friction it causes is cancelled out by the effect of annoying the mostly well-meaning portion of the people who are blocked while not annoying the truly toxic users who will quickly and easily bypass it at all.
I don't tend to participate in twitter fights. A type of twitter fight that comes to mind is people who work at FAANGs being annoyed that people are criticizing their employer's agenda. I saw this against Google with AMP and with Chrome hiding the path from the address bar in a dev channel release. That isn't really coming out of a place of toxicity. The complainer doesn't really deserve to be blocked, but the FAANG employee has a right to keep their mentions and reply threads clean. For minor scuffles like these, a lighter form of blocking is nice.