They haven't been for about 15 years. They are kind of failing the litmus test for "stepping stone". More like "dead end". Not so much that you can never find another or better job, but in such a way that you're screwed out of earning traditional retirement due to spending so many more years than you were planning. Even McDonalds has career paths to become shift managers, store managers, etc. A true "stepping stone" job should be one without significant responsibilities where you only spend about 2 years at before moving on, IMO. It allows you to gain some experience and provide a service/work function, but not be so important that if you fail real bad things happen. This is what the regional industry would like to convince pilots that they are, but I think what they do is at least equal to what "major" airlines do, if not more challenging and worthy of compensation. Maybe that cancels out with the new aspect and not expecting to earn $300,000 the first year, but should be enough that it's considered a legit career. Until they start acting like a legit career I can't seriously think they are looking for quality pilots.

CFIing is a stepping stone to get to regionals.
Regionals are a stepping stone to get to majors.
Majors are a stepping stone to get to UPS/FedEx.
UPS/FedEx are a stepping stone to get to Boeing Test/delivery pilot.
Boeing Test pilot is a stepping stone to get to Nasa test pilot.
I'm sure we could keep going on and find something else...