Pretty easy to do actually... your entire offense is basically on rookie contracts.
Lamar, Andrews, Hollywood, pretty much the entire Oline (Stanley just signed his extension this year), Dobbins, Edwards. That's your QB, your entire Oline, your two best pass catchers, and your top 2 RBs... all on cheap or rookie contracts. That doesn't happen very often.
In 2-3 years, it'll be entirely flipped. Stanley has a huge contract. Lamar will have one. Either Andrews or Brown will get one (possibly both, but I doubt it), and you'll have decisions on the Oline with guys like Bozeman, who I think have earned decent money.
Meanwhile, two years from now, on defense, its basically Marlon and maybe Peters as expensive players. Campbell and Williams will be gone, you won't have a single linebacker on the roster making more than like Queen makes, your safeties will still be relatively cheap.
We will be flipping the script soon. We will be draft heavy on defense by the time we hit 2022-2023, and the offense will have a lot more of the spend and will get a lot less of the draft resources because of it.