Crimea didn't want to be part of Ukraine anymore and who could blame them.
The Donbas region (mostly Russian-speaking people) also wanted independence and got shelled/bombed by the Ukrainian forces for eight years (in spite of the Minsk Accords, now known to be a bad-faith negotiation on the part of Ukraine and NATO to give Ukraine time to upgrade its military) until Russia stepped in. Even then Russia agreed to a peace deal that would have made Donbas independent, not part of Russia, but NATO (specifically Boris Johnson) interfered so they could get the proxy war they wanted all along.
Ukraine was never getting Crimea back and now they've lost the Donbas as well.
I hope Taiwan learns that lesson and stops being NATO's little bitch or their fate will be just as regrettable.