I've tried the opposite, paid everyone the same. But there were clear differences in ability and more importantly outside options. It became a problem when it came to retention and the business didn't have the ability to overpay everyone to keep the top performers.
More broadly than that -- it's not that you need to pay everyone the same, it's that you need clear structure around how your pay works.
An example that became a problem with one previous employer was that they kept saying "performance" was their only determining factor for pay, after it had come out that exactly one person on our team had been offered bonuses as a performance incentive.
It's not actually performance-based if you have different and better reward structures, or if you can't/won't explain why gaps exist.
I'm not answering a pitch that says "$100K-$350K salary, final decision based on vibes" but I will if it says "$250K-$270K salary, needs 10 years of experience leading X kinds of projects and proficiency in Y, Z".
It does make me wonder what would happen if you put out 100 different job adverts split apart by £1,000 increments. I'm sorry you aren't suitable for the 100k job you applied for but would you consider our 97k role instead?
If you want juniors to fill out your team, why are you getting a bunch of seniors?
If I'm building a team, I don't need everyone at the exact same level. I want a mix. I want some juniors, some seniors and a tech lead. The job description is the same, I'm not writing 3 or 4.
If you think every junior/senior/staff has the same ability, you're delusional. Two people can broadly fall into the same bucket but be very different in terms of output.
As an occasional hiring manager, having this sort of flexibility sounds really nice!
Unfortunately I have to define my requirements and justify a fairly narrow range when I want to add to my team, so it's not something I get to enjoy. There have definitely been candidates who stand out from the crowd and have higher expectations, that I have not been able to offer to.