Back then, upgrading meant something for the users, like QuickLook, TimeMachine or for the first time in life I saw a new OS actually take less disk space and was released primarily as optimization of the previous release as in Snow Leopard.

Now I don't bother to watch their keynotes as they're too boring and I'm productive on High Sierra and I don't see any reason I should upgrade and cause unnecessary annoyance. How boring Apple software have become.

Is there a reason to upgrade these days? I don't need SideCar as I connect my laptop to a bigger display.

Same here. Really miss USB-C for charging but that's my only complaint.