Depends on the demographic you are trying to attract on the platform.
I've done a little bit of tech recruiting and I can tell you this: top engineers, no matter the level, get a lot of offer. And they won't hesitate to sort by compensation (unless of course it's SpaceX).
Really, there are two kinds of businesses out there: those that try to make money playing games with compensation and CoL adjustments and those who make money building the best software out there and scaling. The later won't have any problem giving a number: they need the talent right now to scale.
The most amusing, puerile trick goes somewhat like this:
Looking for junior full stack dev. Expert at query optimization, scaling, python, etc
Junior?! Add the word 'expert' once, and by no means is it a junior role.
I recently had a recruiter approach me with a job description such as:
"Able to mentor junior devs"
along with
"Make key decisions" about this and that, peppered throughout the job description.
Ah. I see. A management role, under the guise of a 'junior' job title. On top of this, my linkedin shows 10+ years experience!
Why are you even calling me for a junior role to begin with? Well the answer is obvious. Keyword search, without even glancing at the linkedin profile.
Then on top of all of that, the pay is below the average junior role position locally. Wha?!
Precisely what are these people looking for? An "extremely intelligent", "driven" and "highly capable" dev, combined with "gullible" and "easy to trick"?
And even if you find such a person, what's the point of it all, when they get offered 2x the salary in 3 months?
I just don't get it.
In most cases, it's possible to find feedback from past employees on Glassdoor.
I definitely think there is a market for figuring this out and mashing it up on job pages with a browser extension.