If you post something that wide we're either looking at a sales position or at a company that does not differentiate between a Jr. and a Sr. Developer and lumps them all into Developer.
In itself it might be enough of a red flag not to work there.
Why can't a project just need developers? Maybe you need 2 or 3 across many skill ranges.
I think the best option is different posts with different salary ranges... but I do see how that can be a pain to copy paste data around (say 3 postings x 10 job sites = 30 copy pastes of the same data with a few different skills and a few different numbers)
In itself it might be enough of a red flag not to work there.