Up until recently specific timewalking vendors were selling armor for players of specific level ranges and access to content was somewhat limited if you were below an appropriate level.
Legion was 50+, Cata was 40+ and Outland had a cut off for player levels below 30.
Currently all of the individual timelines (holiday events) require 10 as minimum player level to queue for dungeons and to access items on corresponding vendors (classic vendor at least).
Last week for example, a level 20 (or even as early as lvl 10) could queue for (timewalking) Burning Crusade dungeons but opening the trade window with the timewalking vendor located in Shattrath, they could only see some items, not even all of “cosmetics”, but none of the items with power stats were shown to me. I would suppose we are yet to find out if rules have been updated for other updated vendors in the future, probably not.
Intended or an oversight? It does not seem very consistent to me.
Also on the topic of mounts, both from dungeons and from vendors - they have different level requirements to learn them. Some start as low as 10 while others ask for 27+. Why is this still a thing?
Last on list are the new tabards - last week it was Tranquilien and Area 52 tabards. In two weeks there will be two new ones for the WOTLK factions. Is it absolutely necessary that some of these require EXALTED reputation in order to buy them from the vendor? Can’t you for convenience sake just make them COSMETIC? The reputations in question aren’t even that hard to farm. Before we receive full account wide and shared reputations, could these tabard requirement ask for achievements with a specific faction instead?