And it was equally legal for companies to drop you from consideration for a job if you refused. :/

That's how price discovery can work in markets.

"How much is that tomato?"

"$5"

"Yikes. Too much for me. Thanks for your time"

And that's exactly how salary negotiations work now -- the applicant can name an expected salary, and the employer can respond accordingly. The only thing that's changed is that what you've been paid in the past doesn't have to be a part of that discussion.

It's a bit more like:

"What did you pay your previous supplier for those tomatoes?"

"$4"

"I will charge you $3.95 and nothing less."

Is this actually happening? After a good interview, qualified employees are being turned away by companies in the later stages of the interview/employment process, simply due to candidates refusing to divulge their current salary? I mean, I'm sure it _has_ happened, not sure if that's a strong argument though.

Impossible to know, because employers are not required to share the reason for dropping candidates from consideration. Candidates would need to speculate about the real reason, but I can tell you with pretty high certainty that it has happened to me at least once.

I'm sorry if that may have happened to you. In my experience, this has never happened and, if anything, I was given a substantial bump above the number I gave as a current salary. I guess one anecdote vs. another. I dunno, we'll hopefully see whether or not this actually achieves its intended goals or not.