I don't think any of your concerns are necessarily (important qualifier) driven by use of OI data on the employer side, and the use of the typical salary estima

I don't think any of your concerns are necessarily (important qualifier) driven by use of OI data on the employer side, and the use of the typical salary estimate services on the employee side. Of course there are going to be bad actors and toxic workplaces where the data is being used to lowball. I don't deny that it happens. I don't think those that do are going to be able to survive long, because once the word is on the street that a company is doing that it's gonna be very tough for them to hire talent competitively. FWIW, when I mentioned "bad look", I meant it in the extended sense that you're talking about here, so I agree that employers should never do that, and even that it's a warning sign. I think it definitely impacts the culture of a startup in a negative way and it's a horrible way to treat people.