it inevitably adds toxicity to people’s behaviours. You are tempted to quote when you should be replying, and so you speak at your audience instead of with the person you are talking to. It becomes performative. Even when doing it for “good” like ridiculing awful comments, you are giving awful comments more eyeballs that way
mastodon didn’t have quote posts because:
source
Some mastodon apps do support quotes though, by loading any linked toots in the posts themselves