1. The offers I got were abysmally small and out of touch with the market even when adjusting for my experience and local cost of living.
2. Most places were either extremely poorly reviewed on glassdoor, or were not hiring junior/midlevel developers.
3. Places I interviewed at were using ancient software stacks from 2000-era that would have hampered my professional growth.
Until all these things are fixed and accounted for there is no way brain drain is going to stop. I literally spent 4 months interviewing, fully willing to relocate in the general Midwest to stay in a smaller more affordable town within reasonable driving distance of my family. If people want to keep smart people around, give them reasonable offers in line with the global market, and take risks on junior developers.