Even with Firefox etc. attempting to destroy it, switching to MacOS for my main OS did more to improve my productivity than any other single technological change I’ve ever done.
Glad 5K coaxed me in that direction, or otherwise I might still be stuck in terrible Windows hell or working on the perpetual-tweak OS, Linux.
I still use those OSes, don’t get me wrong. But most of the time I am in MacOS and it’s much better.