See I never had the love affair with XP. I always preferred 98 SE. XP was bloated, slow, and too idiot proof (constant bubble notifications telling me my system needs help, the storage is low, etc) and at the time I despised Luna UI (it was too early for skeuo, and it ended up looking quite cartooney, Fisher Price looking).
So I clinged to 98SE until late 2011 when I couldn't run modern Flash anymore (was using it on Facebook a lot at the time playing games like FarmVille) and many sites going https made the browsers all break. That was on a 'free' Compaq Deskpro I found in a dumpster (why people toss perfectly good machines away is beyond me). I then got exposed to Vista and 7 which are much nicer in the UI than XP could ever be. The only things wrong with Vista were the Wifi bug (unidentified network local access only) and slow boot times (30 minutes before you get a usable desktop). Windows 7 was peak Windows for me. Not XP. I got a system still running XP, with modern browser such as MyPal, but it's still ugly as I remember it. It looks very...well, 2001. Vista came out in 2006, but looks totally futuristic compared with anything modern.
To me a smartphone could never replace a laptop or tablet. They're too limited and impractical to use like that. Imagine trying to do your taxes or spreadsheets or multiple page Word documents on a phone and hitting the wrong gesture or button on screen and losing everything! There's a scene from the movie RV of the main character typing a report on his BlackBerry and spending all night trying to send it via email, and the frustration he experiences would mirror mine doing the same thing. A smartphone, no matter how big it gets, can not replace a tablet or laptop. They exist for different use types. Sure, a smartphone can converge radio, phone, messaging, camera, notes, calculator and so on, but it cannot be a laptop or tablet. To even try to watch video long-term will make your eyes as bad as those who spent hours watching the baseball game on a 5" Sony WatchMan TV back in the 80s.
The best analogy to remark how stupid it is to use a phone as a computer is this: Imagine replacing your fancy 4K 70" TV with a 13" Black and White CRT TV. Sure you can watch the same crap on it, but it will be a tiny little screen, no colour, and low resolution. Impractical in the modern world. Doable, sure, but very, very uncomfortable.
Heck, I was still clinging to a Nokia 5185i until 2010, because that phone worked. I had the menus memorized by heart and could use it blind. Yeah, it had a flat UI design (B&W LCD segment display) but I only had frustrations with anything like a Moto Razr. It wasn't until the iPhone 3GS that there was a perfect UI and phone to upgrade to. But like with that Nokia, I haven't found anything newer to replace the 2010 tech.