Why?
It seems like there are two options:
a) The "founder" of the code disappears in to the ether, and it is the equivalent of "version X only";
b) The "founder" stays involved, and if GPL 3 is updated, they can choose.
only b is worth speaking of. In b, isn't having someone in a position to make a choice much better than no one? What is the boogie monster that is the worry? The FSF puts out the 4.0 version, with a special "except for boramalper" clause, that lets you specifically monetise the hell out of it while keeping it closed source? I would not lose much sleep over that.
Stallman is a nutcase, in an endearing way (ok, maybe you have to have moved in the right circles). But he has put in place a system that needed just such a nutcase, who established clear black lines that could not be crossed, and who was also writing enough amazingly meaningful code that we needed to take his license seriously, that could then establish the institutions and governance to make it all live beyond him.
I really like this as a suggestion, but getting opensource code that isn't in the LLMs training data is a challenge.
Then, with each model having a different training epoch, you end up with no useful comparison, to decide if new models are improving the situation. I don't doubt they are, just not sure this is a way to show it.