> They dont really seem too, though. Theres a lot of examples of rich people building towns even in these comments. Is there any evidence tech moguls do it any more frequently?

The OP didn't really establish it (e.g. take an inventory of all Americans building utopian cities, and see if tech moguls are over-represented), but I wouldn't be surprised if it was true. The combination of experience with disruptive innovation, engineer's syndrome, and power would seem like a recipe for these kinds of cities, though a less productive one than near-absolute power over some polity.

Also, a lot of the towns mentioned in the comments pre-date tech moguls.