If Islands are in unlimited supply, so would instance housing. The insides of housing already are instanced, and we've already seen that literally every player on the game can get a free island with no upkeep that can hold more outdoor furnishing than any house can.
Its not only entirely feasible, but completely standard. Games have been doing it for decades, games even older than FFXIV have done instanced Houses.
FFXIV itself even has a form of instance housing, it just this nasty problem of segregation of problems and solutions and never really implemented it in a way that makes sense.
I just find its hilarious that its taboo to bring this up, and its taboo to expect this completely standard feature from a Subscription based game.
Not only have way older games landed on this solution, but all the pieces of it already exist in FFXIV.
Its not unreasonable, its completely achievable for the game, the developers are quite literally just choosing not to do it.
It undermines every new housing design, every new furniture design, but they chose this none the less.
Its either a misguided artistic choice, or they do it to force subscriptions to remain active.
But if the game can handle near-infinite apartment interiors, and quite literally infinite islands, its completely, 100% feasible and realistic.
