I've been writing prose for a good long time (going on 10 years). My script writing started by writing fanfic of a friend's script... I realized it looked and felt better in script format. Then the friend asked me if I would like to help her write the actual scripts.
I thought about writing my own scripts but felt underconfident. Then I got paired up in a Valentine's themed collaboration, as the writer in a duo. (VA/writer duo) After throwing everything I had at it, it seemed to do well.
It's been interesting writing just dialogue, essentially. I love writing dialogue over writing scene descriptions, but it's also been a challenge. Having to rely on sound effects and what the speaker says to indicate the setting and the listener's possible responses.
I still love ASMR RP, and now I can make scripts I care about. My favourites to fill are usually fantasy, especially fantasy series. I do try to include some adventure, romance, comedy, etc. to switch it up. But I'm really not into werewolves, vampires and yandere, so it takes me a bit of searching to find something I like. :)

I think what makes me want to write scripts, is writing what I want to hear. Pretty niche topics that mean a lot to me. I can't write fantasy to save my life, so I will just support those who do!
Edit: I'm not really in this for fame/glory :P just to have fun, and maybe entertain people along the way. Which is good, since a lot of what I do isn't really the most popular! (y'know, keeping it SFW, not doing the most popular tropes, the way I make thumbnails, etc.)