Like in video games, theres a quality bar based on difficulty to enter said medium.

Because the fediverse is (reletively) harder to navigate and sign up for, the users whove done so sucessfully are usually of higher quality.

With games, i have a self made rule on toxity of a game, which boils down to if a game has the following:

Low system requirement, easy to start/access, free to play, pvp, low skill requirement, low average age, then a game is going to be toxic.

The more checkboxes it checks, the likelyhood that something will be more toxic.

Take for example, someone playing league of legends is likely going to be more toxic than someone who enjoys an arbitrary RTS game. Both have you play against other players in strategy, but the lower skill floor of league (only requiring the user to control a single unit) vs a traditional RTS (controlling an army and production) has a different skill requirement level.