China definiately has the upper hand when it comes to exploiting the natural human resources that would otherwise be thorns in the political landscape.
I also think the comparison is wrong to begin with: I doubt you will find prisons in China that allow inmates to have a TV in their cell, or access to Xbox or other videogames.
So no it is not "whataboutism", which a bs term anyway because it is almost always used in situations where someone implicitly claims that the US cares about human rights and that's why US atrocities must be brought up as counterargument.
https://www.ft.com/content/c78b69e3-82bd-4f72-881c-12b2ca1ce...
Those agreements really only got started with the Berne Convention-- mainly creative works-- and the Paris Convention-- basically industrial patents. (Yes there were some other smaller agreements before, but these brought things into much larger scale with many, many more signatories to the agreements)
Besides, your line of reasoning amounts to "Other people got away with bad things so it's not fair that I do to" As a parent, I spot that line of logic often in with my kids, and it doesn't hold together very well there either.