I run production under windows (Server flavor) and never had this issue, even on Win10, I use Unix too.
So IMHO I doubt we can blame Windows OS itself.
disconnect() does very little: close socket, which is the relevant action toward TWS, then do some internal resources cleanup, resources that will anyway be erased if you exit ungracefully.
BTW Windows does always close all sockets for you when a program exit (or crash).
Of course calling disconnect() is the good practice, but missing it on exit should not lock up the port.
A zombie program ? A Python package ? A disconnect or connect of a wrong object ? (of lack a parameters ?)
