In regards to Super Bowl Wins, in every year that Brady won, he had a Top 10 Defense in Points per Drive Allowed, and in his entire career he only had 3 seasons with a defense ranked 20th or lower in this metric:
(2002 - 20th, 2005 - 22nd, 2011 - 21st)
He had 3 more seasons lower than 10th:
(2010 - 16th, 2012 - 12th, 2022 - 12th)
This means that in 15 of his 21 seasons, Tom Brady played (Spent one season on the IR) He had the benefit of a Top 10 Defense in terms of preventing points each time the opposing offense was on the field. (If you average out every year, the average rank of his defenses is 8.6, If you average out those 15 seasons of a top 10 Defense, the average rank is 5.2)
Since 2001, the following QBs have won Super Bowls having a defense outside the Top 10 in Points per Drive Allowed:
Peyton Manning (2006-30th)
Eli Manning (2007- 15th, 2011 - 24th)
Drew Brees (2009 -15th)
Nick Foles (2017 - 14th)
Patrick Mahomes (2019 - 12th, 2022 - 21st)
Mahomes entire career so far in this metric of defensive assistance:
2018- 28th (Lost to NE in AFCCG)
2019 - 12th (Super Bowl Win)
2020 - 13th (Lost to TB in Super Bowl, utterly destroyed OLine)
2021 - 19th (Lost to CIN in AFCCG - Overtime)
2022 - 21st (Super Bowl Win)
2023 - 3rd (Super Bowl win)
Average: 16th
Comparing Mahomes defensive support to Josh Allen's and Lamar Jackson's defensive support (playoff opponents this year with sizable data):
Josh Allen:
2018 - 10th
2019 - 2nd
2020 - 16th
2021 - 1st
2022 - 5th
2023 - 6th (AVG: 6.7)
Lamar Jackson:
2018 - 2nd
2019 - 5th
2020 - 4th
2021 - 11th
2022 - 9th
2023 - 1st (AVG: 5.3)
Conclusion: Mahomes is more successful than his competitors even with significantly less defensive support. (We all knew this, but it's always nice to have numbers to quantify it.)