In the past it was often difficult to convince employers that you could actually make the transition to a jet from a turbo-prop. The old nonsense about "you can't fly a jet unless you have flown a jet" was put about by ex-military types as a way of leaping over the rest of us plebs down there at FL 210 in all the bad weather. Thankfully, we now know that jets are actually EASY to fly and anyway you already have jet time on your c.v.
As someone said here, these days they want you rated in a specific type anyway. AND usually current within the last six months.
My advice, for what it's worth: If your job sucks, look around and if the best on offer is a turbo-prop job, provided that it offers an improvement in your overall well-being, go for it. I have switched back and forth between jets and turbo-props several times in my career with no problems, so going to a TP won't cause your brain to somehow atrophy. If anything, changing types every few years does wonders for the skills.