"It's ridiculous that he hasn't been hired yet," the Washington Football Team signal-caller told Terez Paylor of Yahoo Sports. "I know that the interview process is weird with the (Chiefs) still in (the playoffs), but, regardless, I don't see how you can excuse it."
He added: "I think Eric's No. 1 quality - and it was apparent the first time I met him - was his leadership. Leadership ability, a true leader of men. He's a guy that had played for a long time, was a great teacher, commanded respect because he gave respect also."
Smith worked with Bieniemy on the Chiefs from 2013 to 2017 while the latter worked as the team's running backs coach. He was then promoted to offensive coordinator in 2018.
The 36-year-old praised Bieniemy's relationship with players and knowledge of offensive systems.
"In the NFL, you have these good-luck coaches," Smith added. "You're about to take the field and (they say), 'OK, good luck.' For me, I was always like, 'Why aren't you going out there with us? Aren't you in it with us?' For me, EB is the epitome of the opposite of that ... He's a guy that there's not a facet of the game on offense that he hasn't been incredibly involved from protections to the run game to the passing game. He knows it all."
The Houston Texans remain the only club of seven in search of a new head coach this offseason that hasn't yet found one.
Bieniemy was reportedly one of the top choices for Texans quarterback Deshaun Watson, but Houston didn't make the coach a priority early during the interview process. The team only met with the 51-year-old earlier this week.
Bieniemy has helped turn the Chiefs' offensive unit into a juggernaut alongside head coach Andy Reid. Kansas City, which is set to play in the AFC title game for the third straight year on Sunday, has finished in the top six in scoring in each of the last three seasons.