Also, treating Marxism the way you suggest empowers the people who will use association with Marxism (which whether or not people who think Marxism had good ideas avoid the name, people who don't can still draw the connections) as an attack against an idea, leveraging the failure of Leninist societies to suggest that anything associated with Marxism is bad. So, no, I'll continue to point out that that involves not only the ad hominem fallacy, but also the fallacy of equivocation.
Giving in to people who are trying to cloud the meaning of words is the linguistic equivalent to negotiating with highjackers. You can do it, but you just make the job easier for the next highjacker.
I know it's a scary moment, where it feels like words have lost their meaning and insanity reigns, but that's just the zeitgeist. Words still mean things and that still had power.
No, they mean the dominant economic system of the developed West in the mid-19th through early-20th century (since replaced in the developed west by the modern mixed economy which is an unstable form with a danger of reverting back to capitalism because it retains central features of capitalism.)
What China has is a transitional form that is somewhere on the map between totalitarian centralization through a kind of neofeudalism (that relates to classical feudalism in the same what that Leninist/Stalinist/Maoist totalitarianism relates to monarchic absolutism) to something like capitalism. Which is certainly progress, just as Marx recognized that the transition from.feudalism to the kind of capitalism he and other contemporary socialist critiqued was progress.
But that it is progress from something worse earlier doesn't make it the ideal end state.
> Did Mao not try hard enough?
Mao tried quite hard at completely the wrong thing. Leninism and it's descendants abandoned key tenants of Marxism to create something that either (in the overly generous view) they thought could work in very different conditions than Marx addressed or (in the more cynical view) as served as convenient propaganda for authoritarian populism in the societies in which they operated.