I am an old fart that's been working with DOS and Windows since the early 90s and I personally don't care for UWP. It's fine but it doesn't seem as performant as WinForms.
I personally don't see the reason to compete with Apple to try to make Windows look like OSX. I've never been a fan of the Mac OS and one thing I've always liked about Windows is it never fooled around with being beautiful. It just was.
With UWP it feels like Microsoft is emulating Apple, though, and people seem to be happy to go along with it. That's fine, and it's not like I'm not going to use an app because it's UWP but by the same token, sometimes UWP apps are very pokey.
I was glad to see Microsoft add support for bringing desktop apps to the app store, and I was excited to convert my own WinForm apps for the store. But it's hard to compete with UWP apps in this day and age.
Which brings me to my point. I've removed some of the apps we've had on the store for a while because no one is downloading them. We've been working on a new app which we don't plan on releasing after all. It's not worth the effort to support apps to give away for free to just have them ignored.
And I'm not bitter. I'm glad Microsoft has a platform where we can release our apps and make them available for free. It's a good store with lots of apps and since we're not advertising, we can't compete. That's just the way it is.
So going forward we plan on supporting the apps we've left on the store, but it's unlikely we'll release any more.