The film is a satire of fascists propaganda, and as good satire often it, it is also an good example of fascist propaganda, just like Snow Crash is satire of Cyberpunk while being a good Cyberpunk.

The book isn't exactly fascist though. Verhoeven said he didn't read the book and does not plan to, so he is satirising somewhat superficially.

Heinlein did explore a lot of various political systems in his books, and I think Starship Troopers is focusing most on voter engagement - how people who vote should know something about what they vote on, and that is why only those who served (which includes military but also other "national service" like being a worker colonising planets or postman or whatever) get vote.

Is that fascist? I don't think so. Is it a good political system? I don't think so either but it is a good enough idea for a book.