I'm as puzzled as you are about exactly the same things.

I think it says a lot that I was genuinely surprised when Swype finally showed up on Play. I'd written it off as forever sideloaded and not totally compatible. Likewise, I have no expectation of niggling bugs in SwiftKey ever being fixed.

As I recall, both Swype and Swiftkey annoyingly expired their beta packages from time to time and both used confusing non/not-quite mobile pages for sign up and to download updates.

Baffling.