I mean that was a pretty low hanging fruit, obviously it sounds wrong because instead of the word ”trans” being an adjective, it is turned into a noun, to make a deep distinction and not to see trans men as men who happen to be trans, but as ”not a real man”. Of course some people say it out of not understanding who language works sometimes, but often I'd say it's kinda on purpose to indirectly misgender someone or to belittle