Just had a look at wefwef and the report option is right next to the share one. Reasonably high chance people are trying to share and just hitting the wrong thing? Especially if their muscle memory already knows "share" is the bottom in that list and "report" has just been added.

That said, there was a bug a few weeks ago (before all the apps, so just on the website) where users were seeing random "report created" popups just while browsing around Lemmy, without clicking or doing anything. I'm not sure what the resolution was there in the end, but if wefwef has somehow introduced a similar bug...