Ctrl-Y is the standard "redo" in all of Microsoft's products. "Ctrl-Shift-Z" does nothing in Microsoft Word.
Windows users are heavily impacted by Pycharm defaulting Ctrl-Y to delete a line. If you're in a state where you've undone many changes and you hit Ctrl-Y then you've destroyed your redo history and a lot of work may have been lost.
Please fix this as a platform compatibility courtesy and a UX need. For reference, here is the notepad++ discussion https://github.com/notepad-plus-plus/notepad-plus-plus/issues/856
Cheers and thanks,