>Also, there's the part about military occupations being considered generally bad.
It was considered a triumph in Kosovo.
Nobody was bothered about NATO troops using military force to make a secessionist referendum happen. Because we did it.
Nobody was bothered that the Serbian constitution prohibited an independence vote. Because we held the vote.
Nobody questioned the result - also 90% - same as Crimea. Because we wanted that vote.
Kosovo's notional independence was as sparsely recognized as Crimea's for decades, even among supposed allies. We didn't play that up as an indication of our friendlessness though - because we did it.
The most substantial difference - that Kosovo ended up a puppet state (Pristina being bisected by "Bill Clinton boulevard" ought to be a clue as to by whom) while Crimea was incorporated directly.
Realistically the conflicts mirror each other much more closely than most people believe. That includes the reason why the west and Russia care deeply about both conflicts and both referenda while neither gives a shit about, say, the Tigray war - because THESE two conflicts dictate Russian and American spheres of influence.