For me the difference was XP vs 10 (I skipped everything in between). XP would bork itself over time. I'd be thrilled to get a year out of an install. W10 is pretty stable unless something goes terribly wrong. Personally, I credit a great deal of that stability to my never allowing it to update itself. Also, I'm not sure if AV protection has gotten better, if people have stopped trying, or if W10 is just more resilient, but reinstalling because of a virus seems to be a thing of the past, also.
If it's just a new installation I only ever used quick formats, so that was never a consideration. W10 sure does install quicker on an SSD, though. It's also true that it installs a great deal faster than XP under any circumstances. I remember waiting an hour for XP to install, and then waiting another hour for it to configure itself. Then spending two hours collecting drivers. Now the whole thing's done and ready to roll in 15 minutes or so.
The downside is that I'm a hardass about wanting my computer the way I want it. I want keyboard shortcuts for specific programs. I want file explorer to look right. I want specific, nonstandard default programs. It's getting everything set up and tweaked that takes so long. Particularly since I'm bad at taking notes, so I have to figure out how to get things setup the way I want them each time, with registry tweaks, GP edits, and all manner of wizardry. And that's assuming it's even possible. Mozilla seems to think that only a particular combination of child rapist, arsonist, and schizophrenic communist would ever want tabs anywhere but the very top of the screen, so every single update they reset them and make it that much harder to put them elsewhere. I can reinstall 10 in less than an hour. I'll be fighting it for a week after, though.