Which doesn't make economic sense for Valve.

They have two clear options:

a) Switch to a true subscription model, but have to build a way to transfer items sold before the switch in payment model, as those have been ruled to be purchases. The gaming community would likely get annoyed with them.

b) Build a way to transfer items. They get to take a cut of this, and can also pass a cut on to the studios, whilst pointing to this ruling as a reason why it has to happen. The gaming community would celebrate it, even if the transfer is ridiculously complex or difficult.

The second option is the cheapest, and can only increase Valve's revenue, whilst they can also placate their partners.

Can Valve take a cut of the transfer? It sounds like the point is French/European citizens must be allowed to resell the game any way they like without any involvement with Valve at all. If the sales/transfers have to go through Valve, it seems that still infringes on "the free movement of goods within the Union."

Of course they can take a cut, just like any physical copy second hand reseller takes a cut. The trick will be demonstrating ownership of digital goods, which is the industry is beginning to invest in things like blockchain tech.

I think I worded my question badly (or I misunderstood the person I was replying to). I thought they were suggesting Valve / Steam would be the only place the sale / transfer could happen.