The false idea that you can’t steal copies has already been dealt with multiple times in this comment thread, and it’s addressed directly and rejected by our Copyright law. A compelling argument needs to be able to accept the fact that taking copies is harmful and demonstrate that the good outweighs the harm.
> it’s not like I will take all your business just like that.
Yes it is, that is exactly what happens when copyrights expire, and the debate we’re having is precisely over whether it should be legal to take all of the business because you’re better at marketing than the original creator. If you don’t do it, someone else will, more so now with the internet than ever before.
> People will still buy from you by default
That’s an assumption that doesn’t stand up to a reality check, it’s rare for media that expires copyright and has a revenue stream to continue providing that same revenue in the face of competition. This is exactly why Disney has asked for extensions.
> If people buy from me instead, that means I am providing some value that you are not providing. And that is good for society.
Not automatically it’s not. The easiest “value” to provide is to steal something you didn’t make, and offer it for less money than the original because you don’t have anything to recoup. That’s not good for society, and it’s why copyrights exist in the first place.