Buy low, sell high. How many years did we see where RB's dominated the first round? Now the Super Bowl winners got to pick the best of the crop this year. That's not overvalued. Contracts are another story.
Old data but this shows RB is the 10th highest position, just ahead of OG. https://www.foxsports.com/nfl/gallery/nfl-position-importance-ranking-value-every-player-053117
I have no problem with taking a RB early - maybe not top ten or anything, but for where they got him and how good he is CEH is a good value pick for the Chiefs. For the next few years, anyway. As soon as he starts making noise about a new contract it's time to move on. Draft running backs and get your money's worth, but don't re-sign them. There's exceptions to the rule - McCaffrey in Carolina is the pulse of that offense, and Saquon will get a payday from the Giants. But by and large RBs just aren't worth the investment of a second contract. Most of them can be replaced for a fraction of the cost in the draft.