

The government was quite upset when De Gaul said “Vive le Quebec Libre”. Similarly when US officials are meddling with Alberta separatism.
None of which is at all relevant, because neither of those involves a foreign government trying to tell us what to do about relations with a third country.
Sorry, but Quebec and Alberta are parts of Canada. Even they admit that they are presently under the control of Canada’s federal government, and were not forced into that at gunpoint (Quebec, in particular, voluntarily joined Confederation when it was first set up and has been a part of Canada from the moment there was a Canada). That a minority of their citizens don’t like that state of affairs is does not make them separate countries.
Taiwan, on the other hand, is not part of China, even if China would like it to be. It is acknowledged as a separate country by the international community, and its government is in no way beholden to that of China. The difference is not subtle and not a matter of debate.