my heccin problematic afab brother (he/him) is truscum and they said they haven’t heard any good arguments not to be.

Can someone help me out??? Just to show them you don’t need GD to be a valid mancave-having, divine afab transmasx, because I can’t really think of a good counterpoint without sounding dumb. their opinion means a lot to me and I’d like them to reconsider :(((

edit: my post is on r/truscum !! im famous :DDD

edit 2: omgggg thank you for the gold kind stranger <333