I mainly use the Mac. It's much quieter, has an amazingly vivid and bright retina display, extremely good battery life, best track pad in the industry and the best speakers on any laptop I've ever had. I like the keyboard, I even game on it. I don't get the whole dongle issue but I'm not a heavy user of peripherals. I have two USB-C port extender dongles should I ever need anything from ethernet to firewire 800. I've used them like twice in the last two years.
The Dell is fine, but I'm just not a big Windows fan. The keyboard is kinda meh, the bluetooth is poor, the screen isn't as bright or vivid and has some light bleed and the build has that cheap plastic feel about it. If it was any more reliable than the Macbook, I think I would be persuaded by the argument about the hardware, but both have had problems, both required lengthy repairs, etc. I have extended warranty on Dell and Applecare for the Mac and I needed them for both.
Laptops fail. My PC motherboard with ultra durable components also failed after two years. Heat and dust and micro-imperfections in silicon will do their thing. Sure, Apple made some questionable design choices. It's still a great machine.