HVAC solves climate control. By that measuring stick, I have been routinely disappointed by indigenous structures that claim to have solved climate control but should more accurately be described as "somewhat mitigating the worst of it at enormous cost to the builder, maintainer, and/or operator." They have a lot more in common with the poorly functioning "thermal battery" than with modern HVAC, which is boring, cheap (by comparison), reliable, flexible, and doesn't even require computers -- a bimetallic strip will do, if you must.

> HVAC solves climate control

At a huge energy cost, because we insist on brute-forcing comfortable climates in cookie-cutter buildings, instead of learning from vernacular/indigenous architecture and using modern technology to augment on top of that.

The real crying shame is that air conditioning units could be used as heat pumps (which can be extremely efficient) with just a few added parts, but hardly anyone does that.

I looked into it, but the added cost isn't really worth the effort where I live. They have such a narrow effective temperature range that it would hardly see any use as such.