The difference is that in the case of hammer vs. nailgun, the old solution (the hammer) is the simple one, and the new solution (the nailgun) is the complex one.
With editors it's the other way around. Old editors are in no way simple, quite the contrary. Emacs is complex, and Vim, while seemingly simple, is complex once you want to change its default mode of working.
As in the case with the hammer, simple tools often work best - but in the world of editors, the new tools are often the simplest ones.
Free storage? You could store a gazillion word processing and spreadsheet documents on a normal hard drive (and back them up on Dropbox if necessary). Awesome software? Hardly (and I've used them for years before I switched back to desktop programs). The word processor still has bugs that should have been weeded out years ago.
So the question is relevant: Why not just use LibreOffice?
So, a laptop where the OS, browser, search engine, email client, calendar, word processor, spreadsheet, etc. are all controlled by a single company that gathers loads of personal information about you? No thanks.