Some of the ransomeware doesn’t even stop the attack after you pay. Some of those even demand more money for a cleaner program the source is selling which, if purchased, will add more virii to the system even if it ends that particular attack.
Oh, yeah. Dealing with these people is truly a last resort. Even if you do, you grab the data and slick your system and scan the heck out of the data before you reload.
The problem is that really good disk encryption is hard to break, which is fine if you're doing it deliberately on your own system but really rough if it's somebody else and they're generating random passwords. Breaking the stuff is quite beyond the average user's means if the code is any good at all. I have a proposed solution, but it involves staking the perps out on ant-hills...