This isn’t to criticize Army or TJ, because they’re hardly alone in having some concerns about the linebacker room. I suspect though that at least some of it stems from a dated perception of defensive structure. If we’re still thinking in 4-3/3-4 terms, it will look barren just by pure numbers. But linebackers are just less important than they once were around the league, and the Bengals (as well as most other teams) simply don’t keep very many of them anymore. When you only have two on the field for most of the game, it’s just not wise to spend roster spots on the position.
As running backs wane in importance, so do linebackers. The running game in general is fast becoming obsolete. Run-heavy teams used to be Super Bowl contenders 20 years ago, and now they’re just “teams with subpar quarterbacks”.