This is the problem mostly from what I can tell. As a senior dev, if you applied for jobs at the same pay as a junior you’d probably be hired in an instant.

If I got laid off today, I'd use this to my advantage. Just apply for and work for two lower-paying jobs at the same time, cumulating in a high total comp.

Actually it might raise red flags. Overqualified for a junior role, won't stay in the position at that level.

If he got 3 interviews off of hundreds of applications, he probably isn't having a lot of opportunity to revise his salary requirements. Unless it's just absurdly high, that probably isn't the issue keeping him unemployed.