Yeah, it doesn't make much sense to spend a first-round draft pick on a running back like Rashaad Penny or Clyde Edwards-Helaire, and then fully guarantee four years of compensation at first-rounder prices, when a team can find running backs like Chris Carson, Kenny McIntosh, and Isiah Pacheco in the seventh round. In addition to the financial burden, there's a huge opportunity cost when a team drafts a running back in the first round instead of a player at a higher-demand position.
Even drafting a running back early in the second round is a lot better than drafting one in the first round, because the team doesn't have to fully guarantee four years of compensation.
I'm against big extensions for running backs too. Before injuries ended Carson's career, people were talking about giving him extensions at $8M+ per year. Even in 2020 and early 2021, I saw that as a terrible waste of cap space, even though I really liked Carson. In the end, the Seahawks signed Carson to a two-year, $10.4M extension in 2021, but he didn't get to play much before needing neck surgery and then retiring. $2.7M of the "dead money" left from Carson's contract came from the Seahawks' 2022 cap, and there will still be $1.736M in dead money against this season's cap. And that was from a $5.2M-per-year contract with "just" $5.5M guaranteed.