This isn’t an abstract comparison. CCP mostly overthrew the existing government and Taiwan was a continuation of that existing system. So for that system be quantifiably better is an issue independent of things like elections.

It’s a clear demonstration that failures like the great Chinese famine simply wouldn’t have happened if the communist revolution failed. That’s a significant political issue, because people from that time period are still alive so they can’t simply erase the memory of it.

Even so, this doesn't change the fact that anything that Maoists could take credit for was done better by the non-ideologue dictator next door.

But the fact that the martial law came to an end largely democratically is good evidence that both democratic reform was easier outside of the CCCP, and that the Taiwanese single party rule was probably not as totalitarian as some people claim.