Plenty, absolutely.Yes, this is true, but let's zoom out a bit here. How many coaches has this NOT been true for? It's rare that an NFL coach completely reinvents themselves. It has happened, is Quinn one of those characters? I doubt it.
I will say this about Quinn though, at least he had some good coordinator hires. I don't think Shannahan coming to Seattle as OC would've ever been a thing under Carroll.
But I will never be opposed to giving a guy a chance beyond their first Head Coaching gig, unless they're a trainwreck type with predictable outcomes (Gase, Josh McDaniels). I have seen enough guys, relatively recently too, win their first Super Bowl after not winning one at their first HC'ing job (Reid, Dungy, Carroll, Belichikck, Arians, Coughlin, Vermeil) to not be opposed to a retread.