Surely you realize how absurd that is? The world where you can't make something at all because somebody else says they had the idea first and now they've legally enjoined anybody else from producing a competing product - even if they never actually release their own - is the world where it's harder and harder for anyone to create something.
Yes, both extremes are bad. Perpetual copyright is bad, removal of copyright is bad. I advocate for a revision of copyright.
Your motivation is that it's your idea and if you don't do the work, nobody else will and your idea will never come to fruition.
But why would I want to do any work, when the end result is that some other company will take what I've invested time and money into, make it faster and cheaper, because they already have all the work I did, take credit for it, make a profit, and leave me poorer and weaker than had I never even started? Yeah, I may be able to go buy the game and play it and see the world I created brought to life, but that's a bit bittersweet, isn't it?
It makes zero sense to say that you have less motivation in a world where you're free to make whatever you can imagine
provided you have the money and resources to do so
than you do in our world, where you can bust your ass to make something truly original, and then Activision comes in, asserts a spurious patent claim on your work that you're too poor to answer in court, and takes your profits (and control of your creation) right out of your hands.
But at least your idea will come to fruition...and isn't that your motivation?
Copyright is what stifles innovation, by taking away people's control over their own culture and ideas. To assert that the lack of copyright "stifles innovation" is both nonsensical and ahistorical, in that it overlooks how the world's most enduring artistic achievements occurred in societies that gave approximately zero copyright protection to anybody.
Perpetual copyright does. Why does it have to be one extreme or the other? Why can't we just reform copyright law, rather than deciding that we'd rather have no copyright law at all, making it nearly impossible for the low-funded, unknown artist to make a living off their effort?