Speaking for myself, but I suspect this applies to a lot of people, the factors that are enabling me to run Linux as my personal computer are:
- The browser experience is now on par with other operating systems. For many people, almost everything they do on their computer is through the browser so this is important.
- Games now work. Every game I've wanted to play has worked on Linux.
- If I want to do word processing or spreadsheeting and I absolutely need the formatting to be correct or want to use the more advanced aspects of Excel, I now have a work device to do those things. This wasn't the case a few years ago, when most people worked on a company desktop machine at work.
Putting that together and subtracting all the annoyances of Windows - nagging notifications, updates that take forever, Windows trying to make my default browser Edge, the greater threat of viruses - why wouldn't I be on Linux? Why wouldn't a lot of people be on Linux?
Honestly, since the introduction of 'tables', pivot tables, Power Pivot and Power Query, Excel is way more viable to be used as a database. Tables in particular mean that formulas fill down and the range automically resizes when records are added.