It's a nice opinion paragraph, but it fails to realize a couple aspects of Tomlin's coaching staff:
He retains a lot of older coaches or coaches with ties to Pittsburgh. These coaches are looking for job security and the Pittsburgh Steelers are the only team in the league that offers that. The author didn't mention if those coaches could coach, because they are not up to date on the exact people Tomlin employs and are making a blanket statement.
When you have coaches like Mitchell 28yrs, Olsavsky 12yrs, Austin 20yrs, Dunbar 16yrs, Jackson 14, Myers 20, Roberts 18, Sullivan 17, and even Flores 14yrs. Coaches are drawn to Pit for job security. If you're good at your job like LeBeau and Dick Hoke, you have a job for life.
It does say something for a Head coach to be able to manage so many seasoned NFL veterans that I'm sure all have big opinions on how to coach in the NFL.