This is a case where the "in 2018" in the title is very helpful, as Googling information about Python and Qt usually returns something dreadfully out of date. (and as other comments note, there are lots of new companion tools/competitors like Electron)
The API still looks messy and unpythonic though, sadly. Look at the basic hello world example. Why do I need to pass QApplication an empty array? Why am I calling a method ending with _ to launch the program? And the fact the label magically attaches to the app through some side effect is also confusing.
Does anyone know if there's any good shim/wrapper around PyQt that has a better API?
Not exactly what you're asking for, but QtPy - https://github.com/spyder-ide/qtpy - is a nice abstraction layer that sits between your program and either PyQt5 or PySide2.