I’m a little late, but I just found out that shiny pet charms are not very useful. So, should I continue to do the pet menagerie, world quests etc. that reward shiny pet charms? Aside from for achievements?
Some of the older quests/WQs that reward Shiny Pet Charms are good for leveling pets. But if you’re not looking for pet levels, completing achievements, or Shiny Charms to purchase (older) vendor pets, then I don’t think there’s much of a reason to keep doing them.
There are more rewards, other rewards besides the shiny pet charms. Some of the Draenor pet battles can drop pets, (Tanaan battles, menagerie?) pet bandages,and a little gold. Get a everliving spore? from the Tanaan jungle and trade it for A LOT of gold!
I had stacks of them leftover from Legion. Only use I found for them was to buy fel piglets and alarm-o-bots for sale on the AH. I don’t bother with them any longer.
Editing to add suggestion: Make a vendor option for trading old pet charms for the new ones on a 10 to 1 basis. This would at least allow players that horded a collection to get some modern value. The 10 to 1 is a suggested ratio to keep inflation of new pet charms down. It could be whatever the devs determine is fair.