Idyllshire didn't used to allow mounts either, and SE changed that
I feel like Solution 9 is just big enough that they might allow mounts again. Eulmore was in an actual city, and Radz was too cramped. Also I miss the days of Idyllshire/rhalgr's reach where you could actually sit around with mounts and see all the cool mounts people have collected, now the only time you see that is when people are waiting for world boss fates