It seems that the one-time reselling clause can be easily abused by the original IP holder to effectively extend their 20 years to 30 years and enable unlimited reselling? Just sell it to a company you control at the end of 20 years, and you get another 10 years. You can then sell the company to whoever is interested in the IP, and they can also do that, as long as it’s the ownership of the company rather than the IP that’s being transferred technically.

It seems much simpler to just shorten copyright protection. Whether 20 years or 30 years, the world will be a more creative place than it currently is.