There are many, more imaginative ways that games could use to "unlock fast travel" if they really tried. For instance an open world game could have a ground mount and then a flying mount later on, even ON TOP of a (less forgiving) network of portals. But I'm digressing a bit since these are not examples that apply to BG3, specifically.
I love dragon mounts.
Well, In WotR you have to do with dinosaur mounts. Although one mythic path gives you a dragon companion. No idea if you can use him as mount though. And another path lets you become a dragon, but technically you are no mount.
