TL;DR: correlation is not causation
But in all seriousness, the advantage that a college degree confers is documented proof that you can study well enough to get your the GPA you got in the field you studied
Meh, I've not seen a single correlation with most criteria under the sun that will indicate how one will be as an employee... Gut feeling has been the most successful for me so far. Obviously a mainline carrier doesn't have the time or resources to use that method...
College degree vs no college, criminal vs clean record, PIC vs no PIC time, high flight time vs low flight time. Oh and Metroliner time vs no Metroliner time.

All of those have shown, to me at least, to have absolutely ZERO objective substance (subjective reasoning is irrational at best and not backed by rational study) to a pilot's ability to pass training and more importantly, if they possess strong work ethic and not be a chode in the work environment.
There is one tiny indication I've noticed though and that is whether or not one was a CFI before or not. CFIs will starve to death if they are jerks. They almost did or left aviation at that point when I was a CFI at least. Someone with a descent amount of dual given in a short amount of time has ALWAYS been top notch in the pilot group so far. Obviously I wouldn't turn away someone without a CFI. This is bottom barrel freight for gods sakes and I need beating hearts in airplane seats!!!

However, ever former CFI that I've worked with has been absolutely amazing as a colleague and as an employee. There has only been one person so far that wasn't a CFI and was just the WORST, and the group before me were all CFIs and almost destroyed the base entirely.
So let me backpedal a little and say that I'm also irrationally using pre-conceived ideas with applicant screening I guess. Perhaps those other criteria that mainline carriers are using as a screening tool have similar statistics. At least at
that particular employer or HR department as to what I think a CFI will bring to my base. I really can't disagree with their methods then...

ESPECIALLY since they have a MUCH bigger sample group to derive their standards from. Does it suck if you feel that you don't fall into statistical categories? Yep, but that's just the way it is.
TL;DR maybe
Meet requirements, don't be a buttface, get jerb. Probably
