Thats possible, but I have watched a lot of scifi that occurred prior to firefly and after, and this was more or less the case. Of course thats anecdotal from my memory.

Now, I just saw, no idea how I missed it, Space Truckers from 1996, with Dennis Hopper! I never would have pegged him to do a movie like that. Its 1000% worth seeing for its sheer nuttery.

https://www.imdb.com/title/tt0120199/

https://www.youtube.com/watch?v=VQOqLOErhZA

Its top of my list of most ridiculous movies.