Yes it’s a fantastic change. As someone who pushed rank in OG Vanilla for the titles and then went hardcore nolife for raiding and Arena in the first season of TBC because I wanted that 330% flight speed for farming(played a Holy Paladin) I love having this stuff account wide. I quit WoW shortly Season 1 when I moved to the EU for school. When I started playing again it was the start of Wrath and my main became a DK. It sucked not having the mount but as they were actual items back then I couldn’t complain much.
When mounts became account wide it felt like a kick in the face that raid drop mounts were account wide and my glad mount wasn’t. This was before everyone seemed to farm up Invincible making that kind of a moot point…but now we’ve got some really rare purchasable/raid mounts and I’m happy they are finally recognising that having some of these great achievements hidden as people have re-rolled classes or factions over the years sucks. I pretty much only tank nowadays and do a little casual PvP on the side since I’m older and don’t play nearly as much as I did at 22.
I always thought they should just keep the current expansion’s glad mounts locked to characters to keep the integrity of that character. Each expansion is almost like a new game with the ever evolving meta/classes. The fact I’ll have a Swift Nether Drake in Shadowlands won’t really matter. It’ll just show I’m an old fart that’s been playing this game for a long time.