It doesn't matter what ultras claim, the fact is that China is not imperialist and this is objectively demonstrable. The myth of Chinese "debt traps" has been extensively debunked by now, and the notion that all loans are imperialist is frankly infantile and an indication that the person claiming this has a very superficial understanding of both imperialism and political economy.
Accepting capitalist investment has nothing to do with the DotP, it does not change in whose hands the state power lies, so this is a total non-sequitur. As is the question of market or planned economy, which is by the way a false dichotomy. Markets and economic planning are both just tools that can be used by bourgeois and proletarian states alike, and they can and do coexist in most countries.