a so-called Chinese Chomsky (an academic type as you say) could indeed advocate either of those two points or variations between them from inside China but for one thing, he or she would have to couch their phrasing in very careful ways to avoid being coercively punished by the apparatus of the state. Furthermore, they'd have a harder time of doing these things today with Xinping's domineering influence at play. In 2005 or 2006, it would have been much easier.

Secondly and much more fundamentally, even if they made such arguments, at no point could they get away with simply advocating for the full removal of the CCP's monopoly on political power.

That's a no-go and it's also something that defines a huge difference between China and, say, the U.S, where an academic or media personality or pretty much anyone can freely advocate all kinds of stuff against the political system without having to phrase it in any particularly careful way.

This includes being able to state that the Republican/Democrat duopoloy is a piece of ineffective garbage and needs to be removed. They might face some social backlash from fans of opposing views but they won't have their legal, financial or human standing destroyed by the government through literal punishments.