I was one of the maintainers (but not inventors) of Apple's autolayout. It's not at all true that "Mac or NeXT" (?) views were absolutely positioned: they used dynamic positioning via autoresizing, which started with a reference layout and then declaratively described how to modify it. This already is well beyond simple absolute layouts and is sufficient for many cases.
Autolayout takes this a step further by adding constraints and priorities for breaking them. This allows you to declaratively and naturally express tricky layouts like aspect ratios or preferred minimum sizes ("I'll have to truncate at...") which are typically special-cased in other layout engines.
Tooling around this stuff is challenging, but the architecture is leagues beyond the simple dynamic layout engines in other UI toolkits. iOS can't fully realize it (no resizable windows) but on the Mac it shines.
I guess I must have imagined a decade or more of seeing absolute positioning in objc code.
I will re-state it. What would cause people to say that Auto Layout is one of the top achievements Apple has ever produced? Unfamiliarity with how other people have approached the problem is high on my list.
Autolayout takes this a step further by adding constraints and priorities for breaking them. This allows you to declaratively and naturally express tricky layouts like aspect ratios or preferred minimum sizes ("I'll have to truncate at...") which are typically special-cased in other layout engines.
Tooling around this stuff is challenging, but the architecture is leagues beyond the simple dynamic layout engines in other UI toolkits. iOS can't fully realize it (no resizable windows) but on the Mac it shines.