Underground housing, underground businesses, etc. Would that be better for the environment + possibly save on energy costs? Also possibly safer in certain scenarios like tornadoes etc.
Potential issues that immediately come to mind are ventilation, earthquakes, and flooding. But it’s not like underground dwellings/basements/etc. aren’t a thing, so maybe those issues have been addressed in ways I’m not familiar with.
I actually quite like the idea of an underground house - it’d be easier to get a nice stable temperature year round and would be much easier to design for bushfire resilience (steel sheets over skylights/doorway, steel mesh over ventilation and you’re pretty set). I could do with my own personal hobbit hole.
I would however want it to be in a position where it does not require pumped drainage. That restricts you to places on a decent slope so you can use gravity to keep things dry and cozy rather than rely on pumps that could break down. Not having a view in the vast majority of locations would also be a downside, but to be fair being able to see a good bit of distance is sadly not something you get in most normal houses anyway.