It's all about the technical features of the platform. Twitter's design is less likely to encourage conformity, so you can find far more insane content in it, but it's also less likely to encourage people to pointlessly discuss popular topics over and over.

Twitter allows for the existence of small ad-hoc communities numbering a dozen people at most, without a designated leader. Facebook groups, subreddits and mastodon instances require that a community has a designated dictatorial leader, be it an admin, a moderator or an instance owner.

The most powerful method of expressing approval - the re-tweet is likely to be used to promote interesting statements. Blind adherence to conformity isn't interesting. Crazy conspiracy theories are interesting, but so is specialized knowledge. All you have to do is ignore the former, (unless conspiracy theories amuse you).