I think you missed an extremely important point here, which is upgradability.
I replaced the battery on my 5 year old Dell XPS 15, and it is basically all new.
If you are someone who likes some tinkering, you can also upgrade the ram, ssd, wifi card, do repasting and undervolting.
I did all that in addition to switching to a linux operating system, and my laptop is performing much better than a new/stock laptop.
Edit: Some have pointed out that you can also upgrade on a MacBook, and you are absolutely right!
Though for my XPS 15 and other Windows laptops, switching batteries is very simple and I paid about 60€ for a 97Wh battery.
Another point is also that you can set the charging limit to say 75% which preserves its life expectancy even more. I am not sure if it is possible on a Mac though..
At the end of the day I think both laptops are amazing, it just depends on what you value more :)