As far as I can tell, the only way Twitter has substantively changed over the past few years is that a small (but non-trivial) number of politically obsessed left-wingers have voluntarily self-exited. Everything else is narrative.
The analysis rests on just nine synthetic accounts, treats thousands of highly correlated feed impressions as if they provide robust independent evidence, lacks a proper baseline for the political content available on X, and reports no meaningful uncertainty, significance testing or adequately powered replication.
I say this as part of the exception. The only reason I don't use X is because they banned me for no reason. Probably not the common case.