Wildstar had this implemented. You’d get a small speed boost while on roads (to simulate the fact that road travel is supposed to be faster than running through woods, etc.)
I know right! People looking for speed buffs then and there while mounts are just the most immersive and most obvious choice.
And no, it won‘t turn to wow just because of it. It‘s a completely different game.Open world PvP would not suffer as it is pretty much nonexistent.And if I encounter a „fight“, it‘s a tedious cat and mouse game of running and healing to the next sanctuary. Being able to move quicker allows for more pvp engagements to happen.