Sun Yat-sen supported Taiwanese Independence.

It's true (exact quote: 「在台灣的中國同胞被日本壓迫，我們必須鼓吹台灣獨立，和高麗的獨立運動互相聯合」).

It wouldn't be all that important, except that as the article linked above indicates, the Chinese Communist Party is trying to co-opt the only universally respected leader the ROC (gg, education system) as a unification supporter. And that's just not true.