> the basic "no-true-scotsman" argument used to advocate for free markets, also known as the Efficient Markets HypothesisNo, that's not the basis for wanting more free markets. The basis for wanting more free markets is that, under conditions where a free market is not efficient (and yes, such conditions often exist), the failure modes of a free market are still better than the failure modes of the alternatives. In other words, free markets are not "best" so much as "least worst" (the worst except for all the others, as Churchill would have said).
In the particular case we were discussing, you were assuming that a transaction was possible (a personal connection) that both parties would value. That means, in a free market, both parties would agree to the transaction, so it would happen. The problem, as you stated it, was that a market did not even exist for such transactions--the parties weren't even aware of each other. And, as I pointed out, the obvious way to fix that is to allow someone to create such a market. Nobody needs to make any decisions about "how social goods are priced" to do that--the market participants themselves will take care of that, by deciding which transactions to engage in and which not. See further comments below.
> The market is producing disastrous outcomes making life unlivable for huge swaths of humanity?
No, it's not. What's producing those disastrous outcomes is the failure modes of the alternatives to a free market. See below.
> The reality is that not all social goods and goals can be priced, or measured, or even understood and articulated in a way we all agree on.
Yes. And in a free market, we don't have to agree on all those things. All we have to agree on is whether or not to engage in particular transactions. If you and I can have a transaction that both of us voluntarily agree on (and that's the definition of a free market, that all transactions are voluntary--nobody is ever forced to make a transaction they don't want to make), then it doesn't matter what the rest of our values or goals are; all that matters is that we agree to make the transaction.
And that is why the failure modes of free markets are better than the failure modes of the alternatives--because the alternatives force people to do things that they don't want to do, or that they even think are very bad ideas, just because someone else in a position of power says so. That is what makes "life unlivable for huge swaths of humanity"--people being forced to do what some idiot in power says, instead of what their own intelligence and common sense would suggest.
> it's literally impossible to base your normative system on the idea that we'll all just optimize for outcomes when that system is non-deterministic
You're assuming that there has to be a single "normative system" that everyone is forced to abide by. And that, as above, is precisely what a free market does not do, and why our current system, which does do that, causes so much misery. Your so-called "public policy discussion" is all about what normative system to impose on people. Your public policy "experts" never even consider the idea of not imposing things on people at all.