The fact that they are in the URL serves an additional purpose for these sites - to identify who is sharing exactly what, and with whom.

(I've noticed that TikTok does this explicitly, providing a different short URL for each share request - it's clean, which makes them easier to share without blocking out a whole chat, but still not wanted)

It's not that I don't mind the parameters, it's that I also mind the URL tracking. And I can do something directly about the URL tracking.

I doubt that’s the case - if you come from Twitter, you sharing the same link with 100 people probably skews their data. I just don’t think it’s that big of a problem yet for marketers to ask their devs to remove utm parameters after they’re logged.

it skews the data in the right direction (from their point of view). if you saw it on twitter, and shared it with 100 people, then (from their perspective) they should spend more time advertising on twitter.