“Can YCT people drink their own wine? “
I found that funny because it’s true. IMO the answer would be no.
It reminded me of a Gemara towards the end of Ketubot (IIRC) where it talks about a deaf person giving a get. The Gemara asks how can a deaf person, lav bar daat, give a get? It answers that the way he got married, he can get divorced – whatever level of daat. Therefore, if a YCT person is a true maamin, then he/she/it can drink his/her/its own wine. And if that person is an apikoros, then they don’t care anyway. Still assur, but a moot point.