I feel like in your last part you are also pre-supposing another third binary (binary 3): the copyright license is the only relevant part to enforcement of a system vs OSS is a community and is bound by ethics as well as laws.

The distinction between ethics and laws is a fascinating dichotomy. "What is the culturally right thing to do?" versus "What is the allowed thing to do?"

The gift economy is already an ethical system like "Take a Penny, Leave a Penny". There are no laws that tell you what to do, you are encouraged to do what is right for you and hopefully what you think is right for the larger culture (the next person into the shop; the next user of the open source software).

Sure, it is hard if not impossible to "enforce" a general ethical system. To some extent that is what laws are for in the abstract ideal, but in regular practice there's a gulf there and we find that some of the beauty of the ethical system is broken when attempted to be constrained by legally enforceable laws.

If you watch someone take all the pennies, stuff them into a Gucci bag, cackle like a villain, and never leave a penny and think "Someone should do something about this", you start to find how slippery it is to add rules to who must leave a penny and who can take a penny and how often and how many variables and edge cases there can be just to try to figure out who is "right" to leave a penny and who is "right" to take one. The open "you know best for yourself in that moment" invite of "Take a Penny, Leave a Penny" disappears exactly in that moment you try to constrain it with rules.

As software developers we love rules and coming up with them. Software is about plumbing for all those variables and building the big charts of the edge cases and solving them. Binary 3 is an easy trap here: people aren't playing the game right, lets add more rules to the laws (software licenses). But it's a break to Binary 1 (forced sharing licenses aren't "fully open") and just as with TAPLAP, it starts to sour the "everyone gifts value to the others to the best of their ability". By adding rules you have to define "value" and "best of their ability" and in doing so you lose that fragile idea of "try your best to do what is right, only you really know what that is".

In the real world TAPLAP is enforced via social contract: reputation and gossip, trust and distrust, dislike and shunning. For enforcing a "gift economy" culture in open source, there are options more like the social contract (industry ethics boards, unethical software company boycotts/reputation smearing). Some of those pieces exist (OSI is an ethics board; ACM has an ethics board; IEEE has an ethics board; FSF likes to think it is an ethics board, but also clearly trusts rules/laws more than open, unconstrained ethical systems) they just may not have enough teeth, especially with respect to enforcing anything like the "gift economy".

So I agree there's a need to better enforce a gift economy, but I don't think it drives a need for other licenses or systems as much as it shows a usefulness in giving more enforcement to the existing "social contract" of open source. Take a library, leave a library. I don't think adding more rules solves enforcement. (And it certainly endangers our principles for "freedom" such as binary 1.) We can and should be able to enforce it even in its "not very explicitly stated" current form as an "ethical obligation" (versus a "legal requirement", very different things). It just is a harder (improv) game to play with less "rules" to play by. (As much as we love rules in software, sometimes it is nice and freeing to take a break and go play an imaginative game with fewer rules.)