Not only should you be able to sell, gift or bequeath digital media - it doesn't actually hurt anyone and, in most cases, it helps the author. (That may vary for digital media like movies and TV shows but bear with me
Old way - I buy a physical copy of a book/CD/DVD. Say it's a series. I lend a copy to a friend. I can't watch/read/listen to it while my friend has it but he likes it so much - he goes and buys his own copy of the series - net gain for the content creator. Problem: I often lose media this way because I either forget who I've loaned it to or they abscond with it!
New way - My and my friend both have Google accounts (for example - could be any online service). I buy a copy of a book from Google Play. The nasty way is for Google to keep the copy server side and I'd need to be online to read it - which would annoy me - but it would allow Google to let me transfer, temporarily or permanently, that copy/license to another Google user. Better than the old way because the book would still be listed in my library but "greyed out" while it was on loan. Unlike a real book, if I don't get it back - it isn't lost because I'd have the option to retrieve the book whether my friend was finished or not
Another of the arguments is that selling second hand prevents the copyright holder from making a sale because they get nothing from a re-sale - but the likelihood is, the person wasn't going to pay full price for it anyway so they wouldn't have made a sale in the first place. They've lost nothing. They potentially gain because the reader/listener/viewer that got the "cheap" copy
I own series of books, hundreds - possibly into the thousands of dollars of books - that almost all started with one a friend loaning me a copy - or a copy I borrowed from the library. The same goes for DVDs of TV Series and movies.
Someone mentioned renting digital media - well most streaming services already let you do that for TV, Movies and Music and last I heard. it was doing extremely well and the artists aren't complaining! Books would be no different and I think there are a few that let you subscribe for unlimited books? Say I can pay a dollar to "rent" a book whenever I want - I still have to be online and then download it for the period of the loan (OverDrive is a great App for free ebooks if your library supports it!) but it still isn't as convenient as owning a copy. Even though I know I can get ebooks free from my library, their licensing agreement means the only have limited copies so they aren't always available when I want them
At the moment I well neither buy real books or ebooks because real books are inconvenient and I don't like not being able to treat my ebook like real books - net loss for the content creators.
I am tempted to try one of those book subscriptions if they actually exist but they'd need to have better content than my local library to make it worthwhile
Nothing will ever be attempted if all possible objections must be first overcome. -- Dr. Johnson