This is why Unsplash & Pixabay are lawsuits just waiting to happen:
Companies using them will get sued
Small companies have already started getting sued because of the unclear copyrights & licenses on the popular free websites.
This is just the beginning of what may become a true nightmare.
AI will make the number of lawsuits explode
The recent advances in AI technology will make this problem explode. It has become much easier for people to match their photos online and start suing companies that use 'free' photos.
Quote from the LONG Unsplash Terms & Conditions
After reading the paragraph above, no companies will probably use the photos, but on the much more visible frontpage of the Unsplash license page, this is what it states:
"All photos published on Unsplash can be used for free. You can use them for commercial purposes.
You do not need to ask permission."