not that surprising really - many, MANY people are fed up with centralized link aggregation/social media/reddit in general & the fediverse is an excellent option
maybe - but the IAU’s definition for a planet indicates that body must clear its orbital path of debris (excepting any natural satellites or or those otherwise under its gravitational influence) - and that immediately rules out any trans-Neptunian objects. possibly there is something between the Kuiper belt and the Oort cloud but our tech is not good enough to detect such a contender for planet as yet.