In any event, they certainly consider themselves to be a country. A rather large one.
The ROC considers Taiwan part of China. The PRC considers Taiwan part of China. The ROC and PRC are rival governments of this one China. The ROC controls Taiwan and a couple other islands, the PRC controls the rest.
The one thing both states agree on is that Taiwan is not a country; Taiwan is part of China. If you're going to be lazy and sloppy about it, you can call the ROC "Taiwan", but neither side actually sees it that way.
Millions of Taiwanese people consider Taiwan a country. I have yet to meet even one in my generation who believes Taiwan to be a part of China. This really is a case of might vs right.
Maybe most Taiwanese people think Taiwan should be an independent country (despite electing the Chinese Nationalist Party to a majority). But by matter of policy and law, it simply isn't. And no one seems willing to change the status quo.
Because that's the only reason Taiwan could be said to agree with mainland China.
Literally. As in, "If you formally declare independence we will kill you all in an invasion."
