Also, they are clunky and slow. For example, switch to a desktop with a universal app open and for the duration of the desktop slide animation, the app window will be completely blank. And then suddenly all the content will flash into sight after the slide ends.
The start menu itself is slow and will miss your first few keystrokes if you try to start a search too quickly. The notification bar is sometimes laggy to open, and so are the universal style notifications.
Sharing across universal apps sometimes works, other times it just opens the target app and sits there. I dunno if this is an app problem or universal platform problem.
I wonder if improving Windows Forms would have been a better strategy. Instead now Forms is seen by many as a dead platform, and UWP is so limited/slow that nobody is developing for it. When soundcloud is smoother/less buggy running on Chrome than as a standalone UWP app, what is even the point of having a software ecosystem, apart from a web browser?