This is an awesome point related to the post I just made as a sibling comment. Solar energy is cheap! The sun blasts us with whatever crazy number real energy folks know by heart. The issue is after we collect it, how do we move it?
If you’ve read Project Hail Mary, the sci-fi part isn’t collecting energy, its the lossless transport.
Hopefully that’s not a spoiler.
A major issue with solar thermal is clouds and dust. PV works fine with indirect light from a dusty panel, but to concentrate sunlight you need a clear sky and clean surfaces. Next you need 2 axis solar tracking to get high grade heat or a complex trough system with a separate working fluid and complex plumbing/heat loss. Next you lose energy trying to concentrate sunlight and from the heat engine itself.
In the end it seems like it should be cheap but nobody got it anywhere lose to PV pricing.
Solar thermal isn't used because solar panels are much cheaper and simpler. In world without cheap solar panels, solar thermal would be preferred form of solar energy, and could be done with advanced technology.