Let's be fair here. The game has a history of elements that are likely far more useful for the DM than the players.
Remember too that when a lot of these elements were introduced (even if they have evolved over the years) downtime was a much bigger aspect of play, especially at levels where spells like Teleportation Circle come into play. The fighters build their keeps and the thieves run their guilds while the wizards and clerics do their permanent magic. Also, players had multiple PCs running concurrently and could level one while another researched a new spell or whatever. Personally, i don't see a problem with the party taking a year off from adventuring so they can upgrade their HQ with something like a teleportation circle. But that requires they have an HQ, of course, as well as not being involved in some massive campaign metaplot that drives ever moment of the game. I prefer the option be in there rather than assuming every campaign was an AP where characters hit max level sometime within a few months of in-game time.