It is impossible to criticize any actions taking place by any entity against a capitalist entity without defending capitalism yourself.
It depends on the purpose and shape of that criticism. If you criticize a communist nation banning a particular corporation’s marketplace from their country on the basis that doing so is a part of a grift that seeks to engineer a national-level monopoly over a particular corporate sector by banning external competition, then, sure, that’s a valid criticism because the intent is innately unethical. But if the Vietnamese video game industry is actively harmed by Steam, an American company, using its vast resources to outcompete Vietnamese publishers, then what is your opposition to this that doesn’t encompass a de facto defense of free market capitalism?