That is an important point, but the solution should be more education about the word "genocide". The Jewish Holocaust was a uniquely horrific historic evil, partly because of the scale, but mainly because of the extreme lengths that Hitler went to exterminate the Jewish race from Europe. Even if he hadn't killed so many, it would have still been a genocide for other reasons. The fact is, "genocide" is not a strong enough word for what happened to the Jews, which is why we need to say "Holocaust" or "Shoah" or something. Even if other 20th century dictators killed more people, it wasn't because of a lifelong, obsessive, race-based hatred like Hitler had.

Anyway, there are plenty of genocides that people should know about, and recognize as such. That should include parliaments/legislatures recognizing genocides they've committed in their own countries as well. Canada is trying to do this now, regarding indigenous people who were treated horrifically, even including many forced sterilizations in recent decades. The votes/declarations regarding the Uyghur genocide would obviously feel more in good faith, if America and Australia and other places led by example, and officially recognized the genocides their own governments have committed in past centuries.

All that said, there's no comparing Xi Jinping with other historic dictators as far as body counts. But he has worked very hard on the Uyghur genocide, and we owe him credit for it.