I don’t think “fascist” or “utopia” are accurate descriptions. With Heinlein, his political settings are less “the world should be like this” than “hey what if the world was like this?”. Again, he wrote it in the middle of writing SiaSL, which demonstrates basically the polar opposite worldview. To interpret ST as fascist propaganda seems a bit myopic.

I think “propaganda” is less accurate than “thought experiment”. Heinlein centered his books around a lot of different political backdrops. Pretty sure he wrote Starship Troopers in the middle of writing the free-love-hippie-commune “propaganda” Stranger in a Strange Land.

Still, probably best not to try to hide subtle critique in something that looks like propaganda.

I’m talking about physically altering the outside world: creating a giant painting, growing a garden, building a house, etc. Anything that takes longer than one day to physically achieve will reset, undoing your progress.

Except everything which physically takes longer than 24 hours.