You call it "economic orthodoxy" but it's really nothing of the sort. There's not even really a technical definition of "free markets" so I don't know where you're getting your assertions.

I think you're kind of gesturing at the concept of "perfect competition", which is rigorously defined and does have technical requirements [0], one of which is perfect information. But it actually doesn't really apply to the tax situation of the owner.

In other words, for political and ethical reasons, there's a lot of reform that can and should be done, but I wouldn't dress up the argument in the form of "economic orthodoxy", unless you're talking about actual economic orthodoxies like lowering corporate income tax and preferring VAT to personal income tax.

edit: I should soften my confidence here, it's been a while since I did economics. At least, I've never heard of transparency extending beyond the good or service being a requirement for perfect competition... do you have a source for that, or can you clarify how it would affect things?

[0] https://en.m.wikipedia.org/wiki/Perfect_competition#Idealizi...