This action is fine to include if the folder already exists – it won’t create duplicates.
Create Folder is helpful for building out a folder structure on the fly and ensuring it exists before attempting to save files somewhere.
*NOTE: Currently only works with the /Shortcuts/ folder structure*
Despite this limitation, Create Folder makes it easier to design and work within a folder system that lives *inside* Shortcuts’ iCloud Drive folder.
This is obviously not ideal for many, but, being so invested in Shortcuts, it’s been worth it for me – most of my files are in the “cloud” anyway, so /Shortcuts/ has become my filesystem in many ways (just be sure to back things up properly).