The other big upside to me was that I could keep working full time while studying. The opportunity cost calculation looks a fair bit different when you're giving up (less quantifiable) leisure time rather than paid work.

I agree that it wasn't all amazing, though -- some courses are great full stop, some are just bad, and many (as you say) really shine only when you go above and beyond.

Still, for those with existing programming experience or an undergrad CS degree, it may not be the best thing to do. If you want to learn some particular skillset, there are more direct paths. It might help with the resume filter, though, and it's handy for non-US people who want to get an H1B for now.