Found this part interesting in the linked article at the end. They don't just take the win losses for sos but incorporate the expected win total from vegas.
2023 NFL Strength of Schedule, Visualization
While there aren’t perfect strength of schedule metrics, using 2023 Vegas win totals is much better than so many widely used metrics that use the previous season’s record.
Here is a visual breakdown of 2023 NFL strength of schedule rankings for each team, based on Vegas win totals.
How Accurate is Warren Sharp’s Model for determining Strength of Schedule?
Looking at last season’s strength of schedule model:
of the 10 teams predicted to have the hardest 2022 schedules, only 2 went to the playoffs (Bengals, Chiefs)
of the 7 teams forecast to have losing records but predicted to have easier than average schedules, 5 went over their win total (Giants, Lions, Commanders, Jaguars, Panthers)
of the 9 teams forecast to have winning records and predicted to have easier than average schedules, 6 went to the playoffs (Eagles, Buccaneers, Cowboys, Ravens, 49ers, Vikings)
Are Strength of Schedule projections accurate?
Short answer: YES
of the 7 teams that actually had the easiest 2022 schedules, 6 went to the playoffs (Eagles, 49ers, Jaguars, Cowboys, Chargers, Chiefs)
of the 7 teams that actually had the hardest 2022 schedules, 2 went to the playoffs (Dolphins, Bengals)
of the 11 teams that actually had the hardest 2022 schedules, only 3 went over their win total (Bengals, Steelers, Jets)
https://www.sharpfootballanalysis.com/analysis/2023-nfl-strength-of-schedule/