I don’t know who (Abigail Thorn? Contrapoints? …Vihart?) but someone was talking about how sometimes that’s the case, that they really don’t have a sense of their own gender. That they’re “really” something like agender, but that it’s just too much of a bother to worry about correcting people. But there are also plenty of cis people deeply invested in their own gender, who really do have toes to it and identify as that gender, but when you ask them how they know, they put it all on external things rather than internal.