The theory probably revolves around there not being a transfer of the file as much as a copy paste of it.
Physical media can be copied but you need blank physical media to copy it to, in a purely digital eco system both the buyer and seller end up being able to have copies of the sold product, which effectively treats the seller as if they are a vendor of the product being sold.
Basically in a world built on copyright law, being able to buy and sell digital media the same as physical media looks a lot like someone scalping the original product to cut into the maker’s bottom line. Megacorps eating it is pretty dope but it significantly diminishes an individual developer’s ability to profit off their own work as well, especially when software development already encourages so much copy pasting to make software that should be working into software that is working.
According to Bush Jr. And Cheney you are now capable of building a super computer dangerous enough to warrant a 20+ year invasion
Depending on the actual condition of all those computers and your own skill in building I’d say you could rig a pretty decent home server rack out of all of those for really most purposes you could imagine, including as a personal VPN, personal RDP to conduct work on, personal test server for experimental code and/or testing potentially unsafe downloads/links for viruses
Shit you could probably build your own OS that optimizes for all that computing power just for the funzies, or even use it to make money by contributing its computing power to a crowd sourced computing project where you dedicate memory bandwidth to the project for some grad student or research institute to do all their crazy math with. Easiest way to rack up academic citations if you ever want to be a researcher!