I have an old 2012 MacBook Pro and it's still functional; it's now running OS Catalina. I upgraded the RAM myself a few years ago. Catalina OS is as recent as it can tolerate.
Newer Mac stuff may be shitty but I don't know; this is still useful for a few more years.
Not feeling the "Mac is shitty" vibe: all Apple stuff I ever bought or got issued at work is still functioning just fine, from iPhone 4s (one of my kids carries it) to 2 yo Makbook Pro (have 3 of these of varying ages). iPhones, AppleTVs, iPads - everything just keeps on ticking with 0 issues, sw- or hw-related. Wintel stuff had much shorter lifespan, even supposedly high-end like Vaio.
Catalina OS is as recent as it can tolerate.
Newer Mac stuff may be shitty but I don't know; this is still useful for a few more years.