Since the warclaw has been so restricted in it's movement and abilities how about enabling it in the personal story and other private instances?
Well, it could make skipping more easy in those, what may not be something Anet wants. But if implemented in such way you are dismounted when you get close enough to mobs (even if they haven't hit you at all), this could work, as a pure QoL enhancement.
Warclaw is for wvw
Use the raptor or the jackal in pve, they have much stronger movement abilities. the warclaw isnt meant to be useful in pve.
Personal story, LS2, and home instance are Core so mounts and gliding unavailable.
HoT and LS3 are HoT so mounts are still disabled, but you can glide.
PoF, LS4, and soon to be LS5 are PoF so you'll be able to both glide and mount.
I too sometimes wish I could mount in my home instance to node faster, or run through low level story missions faster, but I get why it's not a feature.
I do not believe mounts are restricted in pre-pof story instances because of potential map-breaking problems. Those instances were just coded way before the implementation of mounts, and allowing mounts inside those would probably much more complicated (potentialy code-breaking) than just pressing a button.