This is because newer versions of macOS still present themselves as 10.15 (Catalina). A bunch of user agent parsers just assume macOS never goes beyond version 10 and to minimize breakage so they've just frozen the macOS version at "10_15_7". One tell is that if it's Safari 16 it can't actually be on Catalina. Here's a relevant webkit issue: https://bugs.webkit.org/show_bug.cgi?id=216593
