A lot of attunements were effectively restricted by raid lockouts, which is a form of timegating. Daily quests, daily lockouts on heroics, weekly raid lockouts, currency caps, etc. are all forms of timegating. Nevermind stuff like the Gates of AQ or the three literal gates in the Sunwell that blocked progression.
Even RNG drops are a form of timegating. If WoW truly had zero timegating, everything would be a 100% drop rate and you'd only need to run the content once.