That's not how copyright works on physical goods, like books, DVDs, etc... The Doctrine of First Sale is a crucial part of Copyright law. The author doesn't get to control your life because you bought one of their works. If you want to use it in some other way then they intended they don't get a say.

But you are not making another copy with physical goods. You are giving/selling it to someone else. Those things aren't analogical (for the same reason making a copy isn't "stealing" it's at most copyright violation). There is a reason for this distinction. Making physical goods costs money, making digital copies is free (basically). If we accept the premise that copyright holder can exercise control over it there is no reason why you magically should be able to make exactly one copy for someone else once you stop using yours.

The author also doesn't control your life, quite the contrary the court wants to control the life of the author by forcing them to implement ways to move the game to another person/computer/account.

I think selling a computer where the game is installed to someone else is more akin to selling a book or a car or whatever and I doubt anyone would oppose that.

The physical printing costs of a book are a negligible amount of its cover price. Saying that because it's cheaper to make a copy of a digital good it needs new rules doesn't seem like a strong argument.

The author's problem are entirely self inflicted in this case, as it is his own DRM that is making him do extra work to allow transfers.

I know, people here are demanding that after you fill up at an all you can eat buffet, you should be allowed to sell your seat to somebody else.

No they are saying that if you buy a meal, you should be able to package it up and sell it to someone else, which you can do. If I go buy a hamburger, I can walk right out onto the street and if someone else offers me money for it I can sell it. What I can't sell is access, which is what a buffet is, you're not paying for the individual item you're paying for access to the buffet.

So what is the difference exactly if Steam says they sell access to the game for your personal account? Would it that be a good analogy then?

It's a very good analogy. I feel the downvotes come from people who are opposed to copyright in principle. That fine and all but once you accept the premise of copyright then forcing the author to allow reselling defeats the purpose. In case of ebooks for example one could easily resell it like 100 times to all the friends first day so anyone could take a look.

This is especially bad for the authors in case of content based product. If you are selling copies of knowledge you acquired then forcing you to allow reselling means you will have to sell for much higher price or not at all. There are opinions and verdicts of EU courts which makes different rules for content based electronic goods. For example you are not forced to grant refunds with those. I really hope Steam wins the appeal or that courts in other countries won't repeat this verdict (it's not case law in most of Europe so what French court decided hasn't much weight in Germany or Poland or whatever other country.