I feel like if you scroll through any area outside of the fediverse you will here MASTODON SUCKKKKS OMG I HATE IT SO MUCH, it’s gonna fail. or comments saying mastodon will only exist for another year tops. Keep in mind I know in terms of microblogging apps for the fediverse mastodon is not the best, calckey is likely the best but most people only know mastodon
Same reason people fanboy over anything. They have made a personal investment in something, be it time or money, and are now trying to justify it by saying everything else is trash.
Then this gets reinforced by their bubble and more and more extreme opinions form. Reasonable people don’t behave this way.