It’s legal for Apple to distribute Apple binaries. It is not legal for someone else to distribute Apple binaries.
Copying a binary from installer to app folder: not distribution
Putting the binary on a USB and giving it to your buddy: gray area, not worth prosecuting, but maybe technically distribution
Uploading the binary to a GitHub repo titled “Apple binaries here”: obviously distribution
But it's more like a ticket, or an NFT. It's a unique blob that was sold to you. You should be able to transfer it.
Apple's best argument here might be that the blob is meant for one person, and distributing it this way is like sharing a ticket to the cinema between multiple people. I can't enter the cinema, then come outside and pass you the ticket so you can enter it too.