And not copper either. Aluminum.

Conversion is key, hence the use of big ones, not small ones. Break even is 50 km underwater due to much lower resistance, and down to only a few hundred km overland.

In my recent assessment, there were a lot of underground segments, where the same applies.

Related to AC, solar of course is the exception to the rotating generators rule, and solar farms are getting absurdly big, as well as frequently hybridized with wind and batteries (also natively DC).