The honest answer:  nobody cares or would even ask you that question during a professional pilot interview.  Aside from a military pilot job where they can wash you out during pre-solo training, it doesn’t matter.  Primary checkride failures can be dings against you if you have a long string of them without a solid explanation.  But everyone fails a primary checkride now and then.  Now they will care about initial and recurrent type rating checkride fails for part 121 work.

There are a couple of exceptions these days.  Many Chinese airlines who send new pilot recruits to flight schools in the states set time limits for soloing.  Exceed those and you will not become a pilot with them (that and you’re obligated to work in another role within the airline for ten years or so) but the majors here in the states?  They don’t care.

What will kill an airline career are 1) Part 121 checkride failures 2) DUIs 3) felony or drug convictions 4) bad driving records 5) history of aircraft accidents or incidents 6) FAA violations, certificate suspensions or revocations 7) cheating on FAA exams or logbook doctoring or 8) lying about any of the above on a job application.  Basically the airlines want to see that you’re a safe, trustworthy, reliable individual at the controls of an aircraft or other motor vehicle.  They’re also looking to see if you can flit into company culture and fly the way they want you to fly.

Similar to school, the airlines look to your last employer.  Each subsequent increase in responsibility will be what matters.  If you have 3000 hours PIC in a ERJ175 with a good reputation and references from the firm you work for, do you think they will really care that it took you 30 hours to solo in a 172?