Ditto for anyone not using the Apple ecosystem. Better tested drivers installed by default, no OS license hassles, no issues created by malfunctioning (or maliciously functioning) antivirus, top download sites weren't infested with malware (no hunt for the real DL link), journaled FS in the consumer tier for instant fsck since 2002 (vs 2012), no-additional-cost professional-grade IDE since 2003 (vs 2015), one-click backup since 2007, decent integrated movie editing, some truly awesome platform-specific-at-first apps (subethaedit, quicksilver, textmate, coda), solid one-button-away desktop search years before it landed and stabilized in Windows, window navigation with expose (they've arguably been leapfrogged since then with window snapping), unix command line with a decent terminal emulator, emacs movement supported in every text field by default, built-in menu bar search, the list goes on.
I now have both feet in the Windows ecosystem but the transition was rough. If you have used Windows all your life, you have taught yourself to live with a lot of BS. Since you have made the investment it's now a sunk cost and no longer factors into your OS decision. Fair enough, but realize that wasn't the case for everyone. Also realize that you necessarily didn't miss what you never knew you could have.
I use the past tense because MS has caught up on most of these fronts, except for perhaps stable drivers and license hassles, where they are hobbled by their business model rather than technical shortcoming.