They're right. Of their current staff, he's hired:
Jim Knowles
Justin Frye, worked with Day at Temple
Tim Walton, Meyer's CB coach in Jville
Perry Eliano, coached corners for friend and former colleague Luke Fickell
Other than Knowles, these are comfort hires in his sphere, or at the recommendation of friends. And this is who he's hired and churned:
Taver Johnson - Currently Safeties at EMU
Alex Grinch - Took a lateral job with a raise
Billy Davis - Coached Linebackers in the NFL, was not retained by Peterson in Philadelphia and spent 2 years because he lives in Ohio and had young kids. Back in the NFL now.
Kerry Coombs - Abject failure as DC, but Day was too nice to fire him
Jeff Hafley - The "we'll try anything to get the defense right" hire that lasted 1 season. Has driven a bad BC further into the abyss as HC
Yurcich - Passing game coordinator in name only, and QBs, has done a nice job since leaving as OC at pedo st
Greg Mattison - see Hafley, has retired from coaching
Al Washington - Linebackers, spent 3 years and took a lateral move to ND
The rest of the current staff includes Larry Johnson and Tony Alford, who are fOSU lifers not tied to Day, and Hartline who is using Day for as much legitimate resume building as he can. None of these three were hired by Day. That leaves Dennis - QBs, Fleming - ST, and Bailey - TEs. Each of these were analysts under Meyer.
Other than Knowles, a demonstrably good hire, how has Day improved the program? He's brought in shitty coaches who don't stick around, or jammed a square peg in a round hole and failed. Aside from his well defined deficiencies as an actual in-game head coach, he has zero reputation for hiring and retaining good coaches which is imperative to building culture. It will be a slow decline until they finally let him go.