They are welcome to do both. Immediately stop selling and after a X number of days allow refunds at the publishers expense.

To be fair, that was likely some first level support reacting to you trying something that is not supposed to work, as in not supported (playing on Linux).

How the strategy pans out after those talks we will see.

Maybe something like on the protondb website where you can list your hardware, if you want. Partly or completely.

You are more than that.

You also have an ‘E’!