Imagine living in a world where it has to be explicitly said that you are allowed to send someone a free copy of something you wrote.
tbf the confusion is not so much that the author would be allowed to but that they’d want to. people would naturally assume that like with many things people put time into creating, such as novels and video games and whatever else, that the fee required to access it is desired by the author and in some way benefits them.
When I went to university, our lecturer would literally pass around a flash drive with the ridiculously overpriced textbook he was the author of. He was a cool guy who had the extremely valuable skill of turning a dull subject interesting.
Ive had mixed results with this, but one author was really excited (as was i) and we had a good back and forth for a bit after i had a chance to read/digest the paper.