Originally Posted by
rickair7777
The only "small jet" policy which applies is the majors don't want to pay mainline wages and benefits to people flying RJ's (< 100 seats). This has been a consistent theme for many years, and I actually believe them when they say it would not be economical... they've consistently put their money where their mouth is on that.
Bear in mind that all or essentially all labor agreements are structured so the junior-most CA gets paid more than the senior-most FO. They don't want to pay a 50 seat CA more than a widebody FO

At some price point, most pax will drive or take a bus to a larger town... there are few places in the lower 48 where a 2-6 hour drive would not get you to a mid-size town with narrow-body service.
If the problem is a pilot shortage, then mainline won't have to worry about competition filling a vacuum (except EAS, which is not "competition").
In the past there has been a theory that regional flying can be operated at a loss if it fills mainline seats... that has been proven to be unreliable formula for success, in general RJ flying needs to operate in the black on it's own.
That's true, and several other reasons, for why RJ flying is off the mainline list. Keep in mind however, mainline is flying a massive amount of routes with mainline aircraft in slots that are allocated to RJs. Subsequently, the RJs are flying elsewhere in the system. If mainline gets rid of the RJs, those slots then go up for bid to other airlines. It's usually the RJs that get canceled when bad weather starts restricting traffic. Mainline simply can't give up the RJs, they have to operate them at mainline eventually.