Here's the thing regarding original theme sci-fi (and why I'm reluctant to use my setting):
People are lazy.
At least with an existing IP, most of your incoming players will know it and those that don't have the plethora of knowledgeable players to help or can be told what episodes are 'musts' to get the feel for it. Like BSG? You can watch it all, sure, or just the mini-series.
I don't know how often @Seraphim73 and Co had to tell people on 5th World that just because there was nobility didn't mean it wasn't still a very futuristic setting. That yes there's CCTV everywhere. Yes, you grew up surrounded by tech; computers and similar devices are not 'foreign' to you. Etc, etc. All things clearly defined on the website, but enough players were too lazy to read/learn that you had to frequently stop RP to be like 'uh, this is wildly out of theme and it's kinda fucking up everyone else's immersion.'
I tried helping someone else with an original sci-fi game a few years ago. Never got off the ground because so many potential players were turned off by the amount of reading/learning required.
A lot of us love OT Sci-Fi, but there's also so fucking many people out there who won't pay a lick of attention to your setting while also throwing tantrums when people try to correct them.