Somehow I accidentally activated iCloud Photo Library and about 5 GB of my photos now reside there. Since I use other cloud services for my photos, I wish to take these off iCloud.
macOS Photos, however, doesn't let me download my photos:
Your full-resolution photos and videos stored in iCloud may not fit on this Mac.
I have 45 GB free on internal SSD. And iCloud has at most 5 GB of storage. What is happening?