You are very obviously right for individual decision taken as a result of an interaction.
Other commenter commented about decisions taken for other instance's users.
For preemptive blocking (whether at the individual level or silencing at the instance level): looking at the whole system at once, there's an obvious positive feedback loop problem. Trying to see who was blocked by others and doing the same is a thing (see e.g. https://qoto.org/@robryk/109350968946902477). Obviously everyone has the right to do so. However, many enough instances doing that creates a positive feedback loop, so it has attractors and encourages trolls.
So, we have a right that, when used by the majority in one of the simplest ways possible makes the network IMO worse. A reasonable reaction to that is to make a simpler and effective way to use that right that doesn't create the same issue when used by the majority of users.
I have no opinion on whether ufoi is likely to help (and it would be worth little, given that I'm confused by social behaviour sometimes).