Historically they were far right anti communists who ran the military dictatorship, so squaring that circle with pro-unification sentiment has lead to some weird positions.

I was under the impression that they were pro-unification in the “mainland becomes part of the RoC again” sense, not the “Taiwan becomes part of the PRC” sense, so that geometry doesn’t seem complicated to me. I imagine that if that’s changed, it’s only because the CCP has become less leftist while remaining authoritarian, and thus has increased its appeal among right-authoritarians.