The issue with patents being 20 years that it completly stops innovation because even if it's reproduced and improved patent stops it from coming to the market and the patent holder has no incentive to improve anything since it can just rake in the money.
Trademarks purpose is to make brand recognizible and it should exist as long as the company pruduces anything under that brand. Caping it's existance serves no purpose aparting from letting cheap copies to be sold which doesn't benefit anyone.
I think trademarks should be for the life of the company/author. since that's literally their purpose. but copyrights and patents shouldn't last longer than 20 years at most.
A trademark is a name. The point is to remove ambiguity and confusion when multiple people are selling similar products. Ie to prevent name collision. Once the company or person is dead, there is no longer an issue. Having indefinite trademarks will mean we will eventually run out of names, as every name will eventually be taken over many years. By having them expire upon death, the trademark is freed up for reuse.
Perhaps not have it immediately upon death though. I wouldn't mind, say, a 200 year trademark, for instance. Trademarks aren't preventing culture, they're just clarifying names.
Imagine if one person ever in history could be named "Joe". Naturally during Joe's life it's useful to ensure no one else has his exact name. but after he's been dead for 200 years? Do we really need to make sure no one else ever is named Joe?
Look at the Atari situation. Atari is a company that is long gone and everyone knows it. However, companies are propping themselves up as atari because they own the Atari trademark. In the system of "someone holds their trademark even after death", these new atari companies can't call themselves atari. Is that good? bad? up for debate, but regardless no one is confusing them for the old classic atari (or maybe they are haha).
But atari (the old company) surely isn't being hurt by the confusion.
Having indefinite trademarks will mean we will eventually run out of names, as every name will eventually be taken over many years.
This, I think, is the core of the issue for you, correct?
That's not how trademarks work. There are plenty of authors out there with the same name as other authors (like, literal authors, not in the general sense of creators of works). There are plenty of companies that have the same name as other companies, be that essentially the same or actually the same.
This ticks off the Joe example. Atari is a brand, that brand is IP, so that's a separate issue. I'm not sure what you're even trying to say about Atari there, though I'm pretty sure if the Atari trademark disappeared immediately on Atari's collapse you'd just see another company start trading as Atari, which under your prescription would be legal, and the world would be functionally identical in relation to the Atari trademark.
While true, I don't have a problem with entertainment being copyrighted for longer, it's impact on quality of life and health is non existent in comparison to patents.