Now, if I took that valuable three (or however many years) of experience and moved forward with it, that's fine. By moving forward, I mean a national/LCC, good corporate gig, overseas, etc. But leaving a place like Eagle for Mesa/PSA/Compass and hoping for a quick upgrade? I just couldn't do it, and quite frankly it would be a waste of my experience, hard work, education, and ability.
I understand your point, and just wanted to ask a follow up question to get your perspective on it.
Lets say that someone had been at Eagle for 3 years and stuck - with no upgrade in sight and no chance for advancement. That person chose to make a lateral move to Mesa/PSA/Compass and was able to upgrade 18 months later. After 6 years total in the regionals, that person had a resume that included 6 years of part 121 flying, of which the last 18 months were while serving as a Captain. At that point, they would have a much better chance of moving on to something better - like a national carrier. If they had stayed at Eagle (and I am not picking on Eagle - just using it as the example since you mentioned it), they would not have any PIC experience in the 121 world.
In this case, was making the lateral move worth it? If now, why? (I am not asking sarcastically, I am just trying to understand another point of view).