> another geothermal energy idea: dig about 3 or so miles straight down and harvest the heat that is there already

Deep geothermal ought to work. Deep drilling is hard, but it's been done. Eavor-Deep got down to where they got 250C water. [1] That was back in 2023. Not much new since. The problem seems to be that when you drill into really hot rock, most drilling techniques run into trouble. Rock becomes plastic and clogs things up. The drilling tools have problems with the heat. Progress continues, slowly.

There's these guys, trying to drill with microwaves: [1] On September 4, they're going to do a public demo and try to drill a 100 meter hole.

[1] https://eavor.com/eavor-deep/

[2] https://www.quaise.com/

The other issue is that the steam loses energy as it's pumped over a long distance. Iceland and a few other locations are big users since they are on fault zones with hot rocks relatively close to the surface. Even if deep drilling is demonstrated, it's unclear if geothermal power will become geographically independent.