The glad mounts (top what 0.1%?) have consistently had equal to if not more detail than the raid mounts. The outlier here is probably the M Argus mount, but the infernal mounts for Nighthold were a reskin of the gronn mounts, albeit a GOOD reskin.
As of RIGHT NOW 467 guilds have killed Ghuun. If no new guilds killed Ghuun and they all recleared every week, that is still about 4000 mounts circulating before the next raid tier which I am fairly certain is higher than the glad number. That isn’t even accounting for the fact that raid bosses that drop mythic mounts have a 100% drop rate until X.0 of the next expansion. My friend’s guild sold Guldan mounts all the way up until prepatch of BfA.