People don't yell at each other in Mastodon precisely because so few people use it (besides, I've already seen Twitter-like behavior there, mainly on the mastodon.social instance). If mastodon had the same amount of users it would be the same, if not worse, because there's no centralized moderation to lean on.
Mastodon seems fixated on emulating Twitter without questioning if there's anything worth keeping.
This is why the instance I'm on mutes mastodon.social. Interaction quality spiked after that. It works with small numbers and good communities. I have several small instances on my personal mute list because the admins brought all the worst Twitter behavior over. That sets a negative tone and ensures only negative people get invited in.
Mastodon seems fixated on emulating Twitter without questioning if there's anything worth keeping.