I'm not sure who you're writing to, but this is a user to user forum. And people like me are here because the program works perfectly for us and we want to help you with your issues. In fact, I'd expect that if you're having no problems running version 15, you'll have no problems running version 2020 also.
Remember that the bad reviews you see are from people venting their anger and frustration. You rarely hear from the many more people who are having no problems because they're out making videos!
That said, I always recommend test driving the free trial before purchasing to make sure it marries well with your system. I might also suggest that unless there is a feature you want or need in the newer version, you may want to just stay with your current version.
And all of that said, there's a lot to be said about DaVinci Resolve. It's a terrific editor! If it meets all of your needs, why buy something else?