Huh. Well look at that. It's apparently hard to find, and it does appear that you're limited to splitting a "fullscreen" view - i.e., no menu bar, dock, or other windows - but it's better than nothing.
Yeah — not to mention the lack of keyboard controls like Windows 10. Sigh!
spectacle provides these features. But I agree, it should be part of the OS's UX
Since finding out about Spectacle, I don't even really make use of BTT at all anymore, even though it is still installed and running...