The dispute at this point is over how we define a country, especially because Taiwan clearly falls in a grey area within that definition. I claim that they are fundamentally unable to exercise their sovereignty given they aren’t formally recognized as a country by even their greatest allies and benefactors, thus they fail. You claim that they can fulfill the roles of the state, have a national identity, and have various semantic work-arounds for that fundamental illegitimacy, thus they pass. There’s also the question of the legitimacy of their founding, with me saying that the ROC was originally an oppressive colonial military dictatorship, but then you would say that it’s been long enough and their government has changed enough that it doesn’t matter, then we bicker over what constitutes a democracy.
Ultimately the argument would continue indefinitely and I don’t think there’s much chance either of us would be convinced by the other.
As an aside, the point of the prior comment was that surveys of beliefs can very easily be detached from reality, and so aren’t good evidence for claims.
Given that Israel is militarily occupying and actively colonizing Palestine, I would say that Palestine is unable to exercise its sovereignty. Should it be granted more sovereignty? Yes, but that seems as though it will require either the radical reformation or outright destruction of Israel.