Wall of text coming up, as I am pretty p*ssed off at the moment 
So, here’s the thing. Today I noticed that I was at 349/350 mounts to get the achievement and the free mount that comes with it. So, I buy myself a mount from AH for 139k, add it to the mountsjournal… and no achievement.
Then I remembered that I’ve had this happen a few years ago as well, and that I got the achievement by logging in other characters that could have more mounts. So, I logged in my Warlock tailor, my Paladin, my Demon Hunter and a bunch of others: still no achievement.
I do some research, and I find out that you are no longer able to see which of your characters has the most mounts (you used to be able to see that before, no idea when it was changed). I go to the help section, find an article that explains how it works, and that even links to the Wowhead Mounttracker where you can see what toon has the most mounts (the website is totally awesome, but sort of not useful anymore, as ALL your characters will say the exact same thing).
Then I find information that there’s been a bug (for years already, and still doesn’t appear to be solved) that requires you to actually learn a mount on the character with the most mounts in order for it to register for the count/achievement. But how in the world can I do that when I can no longer see what character has the most mounts? The only way seems to be trial and error by going around getting mounts on all your characters, hoping you will land yourself an achievement.
And then… I had the audacity to open a support ticket, hoping for anything other than a standard response. I explained the situation, and the steps I had already taken (like reading the support article, and logging in other characters). And low and behold! I get an infuriatingly standard response, with an exact copy/paste from that support article, telling me to do the things I had already done.
Really, I am beyond frustrated and disappointed. In all the tickets I have opened (and there aren’t a lot in the 18 or so years I’ve been playing) it’s always the same. It NEVER looks like you guys actually read what someone says, and you always reply with a mostly useless and infuriating standard answer. Can you for once please just fix the issue? And if you change systems like being able to see the mount count per character, can you please also fix related bugs, and how the system works? If you cannot see the per character mount count, then it should not be a ‘usable by a single character’ type of achievement anymore either.
I didn’t buy that 139k mount for the mount itself, nor do I care about the gold I spent. I bought it for the achievement and the free mount that comes with it (that every single one of my characters showed me I could get, by being at 349/350 mounts), and I got neither. Is it really too much to ask for you guys to please fix it? Thank you.