I agree with @dominicm - it's important to be able to rule out jobs that can't support you. The rationales I've heard for not allowing that to happen seem to be based on some kind of subterfuge - to me that basically means that the employer is ok wasting some people's time on a bet that they can convince someone else to work for less than they need. That seems both ethically dubious and a bit of a self-own - unless you're a non-profit or a mars colonization program, how long do you think you can retain someone who isn't getting paid enough?
I get that some employers consider salary to be private information, but to me that doesn't speak well of their likely culture and practices
traditionally that's how you maintain structural inequalities