Looking into it now (the past 5 years not counting 2020), it really varies. 3 teams .500 or better would have missed the playoffs last year under the 12 team format, 4 in 2019 and 2018, 2017 would be a wash (only 5 teams .500 or better in the AL somehow lol), and then 4 again in 2016.
Of course, there are a lot of high 70/80 win teams that might have fizzled at the end or just barely got beat out by other teams that made it in I guess.