Ehhh, agree to disagree here. I've read a lot of comments from people (and I don't have the time to dig and say exactly who at the moment) who have made it pretty clear they feel like they can make it work with late rounders and that they're prevalent in the league. I agree with you on that second contract being a pretty scary thing, though.
But even in a "committee," most teams have a lead back or intend to have one. Pacheco isn't part of a committee, and as you mentioned, the Chiefs tried to invest more into the position, the guy just busted. But Pacheco is one of the few major outliers of a successful late pick. The Ravens are very invested, so I'm not sure where you're coming from... they have Derrick Henry. And even before that, Dobbins, a 2nd round pick, was supposed to be their guy if it weren't for injury. Similar for the Bills... they're running a 2nd round pick out there in James Cook as their starter, who is getting the majority of the carries and doesn't have a true competitor for snaps.
The 1st or 2nd round RB is becoming more en vogue as of late.