Several major airports are not part of Indoor Maps - Do you know when ATL, AUS, DFW, MCO, SLC, SAT, SFO, IAD, and DCA will have indoor maps available?
When will more airports be available on indoor maps?
You may have noticed that they regularly announce new airports:
I suppose you have looked here :
h ttps://www.apple.com/ios/feature-availability/
for Indoor Maps Airports
Anyway, that's not the best forum to ask such a question.
Ask directly to apple product support.