Literally in the first paragraph of the link you sent me about the 100 year old law, it said that it was repealed and superseded in the 70s. I don't think you're even reading the sources you send me. Are you just generating responses with ai?
Again, what law is being broken by steam?
First sale doctrine does not apply to licenses, it applies to products, and furthermore you cannot transfer a digital product without copying it.
We can't just say that they're breaking the law as were wish it existed rather than how it actually is, but I agree with your goal, that software should be resellable.