From what I can tell china is "communist" on the basis of majority "public" (state) ownership of the means of production (they tried full public (state) ownership under mao, and concluded that in china's case it would just limit socialism to "poverty socialism", where you may have the moral high ground in principle but in reality the people are starving, or so the narrative goes), and the liberation of productive forces of a large amount of people, from low income jobs to higher income jobs, sometimes using tools like automation and using aforementioned ownership of the means of production to make it be. democratic participation seems to exist too, just not in a western liberal democratic way where parties fight against each other, but rather where internal factions inside the communist party and a few associated parties fight each other, and where change must come from within. china has genuinely, using its own methods, lifted hundreds of millions of people out of dead end poverty, while also defending against hostilities from the west. it's impressive what happened, even if china has also simultaneously committed atrocities, violates human rights with for example their handling of the uyghur muslims, and still has millions of people struggling, for example migrant workers in factories who have basically no future, or the ubiquitous delivery driver who gets paid fuck all. all in all it's a very mixed bag, but it's not all bad.
of course better systems are possible, but they basically built this system "in a cave with a box of scraps" to quote the iron man movie.