As someone who's not a fan of horror in the slightest, but DOES love pulp scifi and expansion- I actually think it fits perfectly. The issue is language, more than anything. The intention behind pulp scifi was never to scare the bejeezus out of someone, but present strange and eerie scenarios that made the reader think.
More importantly, almost any theme with growth or most of the kinks on display here IS horrifying to "normal" people. We who love it sit with that on the daily, so to have a chance to glorify and celebrate that- it's special.
Some buxom babe strapped to a table and shot full of energy rays until her tits fill a room is terrifying to "most" folks- but to us it's a normal day at the office. Unable to move? Horror. Mad scientist? Horror. Ballooning tits? Horror/kink depending on who you ask. A giant woman stepping on someone is "horrifying" to some, and absolute fucking goals to others. There's absolutely no reason not to include the jam theme in the title, especially when it's so important.
Saying pulp sci-fi is "restrictive" is absurd. There's monsters from the deep, robots gone amuck, mad scientists of every description, giant creatures/women, spacey shenanigans, strange new worlds, and so much more. If you can't come up with something to fit a theme that's had examples readily available for upwards of sixty years, that's a you problem. I had 10 days to come up with an idea, prototype, get art, VA, and polish- and I did it in six.
If no-ai use is a last straw for you somehow, then by all means, feel free to participate in some other jam.