why is castrum and praetorium not an instance

[Pintsized]

Well, WOW's dungeon content has been re-engineered where necessary to allow it to be soloed by over-leveled characters, in GW2 the only group instance in the main story' was given a soloable variant after a couple of years, FFXI's level syncs were removed to allow over-leveling.

They're the ones I can immediately think of.

BIG difference though, only the first FFXI expac was locked by having to complete the base game's story .. XIV of course gates basic character progression and all expansion content in that way. .. and only FFXI gated character progression (airships and one of two other QoL features) behind such content.