Because Ukraine has a single unified government excepting the occupied Donbas?
Calling it the Israel-Palestine war would be misleading because Israel hasn’t invaded the West Bank which has a separate/unrelated Palestine government.
To analogize oppositely, it would be real weird if China invaded Taiwan and people started calling it the Chinese civil war.
Its worth adding, TikTok in China (it's called something else, I'm blanking) is entirely controlled on the state and there is absolutely no way that it would be permitted to host any political discussion or advocate mass action not approved by the state. Their "Hey call your congressman" stunt was the most idiotic PR move ever, because they demonstrated that this company is willing and able to leverage the userbase in the US in ways that would never be permitted in "West Taiwan".