There are no purely Capitalist or Socialist economies. Every industrialized nation has a mixed economy. The US is Capitalist-leaning but has a broad social safety-net and financial regulations. China is Socialist-leaning but allows private ownership of businesses and engages in the Free Market outside of China.
However, the PRC today still self-identifies as "Marxist-Leninist". So if one wants to argue that "Socialism never works" they have to address China, Vietnam, Bolivia, and a handful of other countries where Socialist governments have successfully reduced poverty and created healthy economies...
It is irrelevant to me as to how a country self identifies itself. That fact is that all countries which have economic success own this to the allowing, at least to some extent, the operation of a free market.
Not all governments are a combination of Capitalist and Socialist economies. Before 1978, China was a pure Socialist economy and it failed totally to bring prosperity to its people.
Of course, China can’t identify itself as anything other than a “Marxist-Leninist” government. There have been too many decades of propaganda for them to identify themselves as anything else. Trump can “self-identify” himself as a Pro-Democracy politician who respects the principle of government of the people, by the people and for the people, but that doesn’t make him so. What governments and people “self-identify” themselves as does not matter to me.