I think Delta is probably banking on other regional FOs making lateral moves to Endeavor because of the flow. Most CFIs who are trying to get on with a regional don't know or care about any airline beyond the payscale or domiciles. I've told plenty of former students and co-workers to stay away from current regionals only to have them go there and complain non-stop about it. Kids with SJS will take the frist offer they get.

I doubt flow to Delta will attract that many more new hires with no 121 time. It probably will attract some FOs from other carriers who have no upgrade in sight there anyway.