Only thing I ever hear about Mastodon is that you can't say or do anything without random other servers disconnecting you or random commenters yelling at you to add trigger warnings because you posted a picture of food. So I would say that being emotionally abused by German Linux users is in fact a mass psychology experiment.
Its a problem with for-profit social media. The companies use gamification to addict and create terrible trends for everyone involved.
Mastodon, peertube, lemmy, and federated media doesn't do any of these gamblification, gamification, psychological attacks, and more.
To be fair, the techniques should be banned by the FTC for deceptive practices, for everyone. But the kids angle is what's being gravitated towards.
Put another way, it's as bad as your kids texting with random strangers. I know in the last decade the focus has been on all the big tech addiction mechanisms, but people were warning against them well before those came into play.
[1] It was also great for some kids in those days. That doesn't take away from the risks.