Blocking instances has been standard practice for ages on mastodon, it's an important moderation tool to keep radical right-wing instances at bay. Without it, the overall experience would be much worse. Of course there will always be a debate about which instances should be defederated and which shouldn't, but as another commenter already mentioned, everyone will be able to make their choice and find their own little corner.
I have it and I'm pretty happy with it, but for some reason I have dropped this phone way more often than any phone I had before. Idk if this is a me issue, but maybe get a protective case from the start (unlike me)