I simply haven't seen the results you're talking about. A year at a regional to show up on property? I've run into some guys that spent 2-3 years at a regional, but they weren't around much since they were flying planes around with the guard at the same time. Otherwise, most my friends are line check airmen at regionals, or captains with thousands of hours, and they're waiting on a class date where I work.
Are things amazing right now? Yes, they are. I'm going to upgrade after 3 years. I've gained 10% on the seniority list every year. This is amazing, I don't disagree with that.
But it's not a year at a regional and then showing up at a LCC amazing.
That being said, I'll be flying with the new kids this summer, so I'll let you know what experience levels I run into.
Also, expect things to start to suck sooner rather than later. I (don't) hate to be debbie downer, but at some point this ride is going to come to an end. I hope we've all got amazing jobs and United doesn't furlough 2,000 pilots. Again.