Performing poorly is what will trigger the PIP like process, compensation only comes up later. Further, it's rare for an org to truly let a manager slice up their compensation budget however the like (hey you can hire 2 juniors or 1 senior, your call).. so it often doesn't cost your direct line manager extra headcount just because you are on expensive end. Usually headcount is decided, and then the compensation required to fill that headcount is a secondary concern, as crazy as that seems.
Further, it's a rare interview process that doesn't shake out that you are at a lower seniority level than you are representing. Interviews may fail to shake out exact level of technical proficiency but I think most interviews do place you on the junior->senior spectrum fairly well.
Only once in my 20 year career have I almost gotten a job that in retrospect was way ahead of where I was at the time. 15 years later I ended up finally taking a similar job. But they didn't hire me!