Except – The expiration date can be extended by just continuing to use the IP – Ever wondered why movies get remakes/reimaginings every 30 years or so? We meme about them being “Out of ideas”, but really it’s so they can hold down their copyright.

No, that's just wrong. At one point, early Marvel contracts had clauses that allowed the movie producer to keep the contract going if they continued to put out movies. When Marvel got big (post-Iron Man), they had been trying to claw back those contracts. That's why Fox kept putting out an X-Man movie every few years, and Sony kept putting out Spiderman.

But, that has nothing to do with copyrights, and all of the remakes are just shit that Hollywood does for memberberries.