Gotta scrimp somewhere when you're paying your QB $20 million/year, even more so when you choose to invest heavily in all of your defensive stars. Just compare the Hawks' books: https://overthecap.com/salary-cap/seattle-seahawks/to the Pats': https://overthecap.com/salary-cap/new-england-patriots/. On the first list we see a lot of big #'s occupying the top of the list and on the second you see much lower numbers even at the very top. Brady takes the team-friendly deal and restructures regularly, allowing his team to sign the pieces they need, which are rarely big names and big splashes. Say what you will about having the best QB of all time or whatever, but a certain amount of their success can be attributed to Brady not being greedy.
You can even look at the list of QB contracts and the top 10 names are names that haven't been to the Super Bowl since their signed their respective extensions. It's still a team game.