On the contrary, it's easy in our tech bubble to assume that everybody else uses a computer just for mail, netflix and spreadsheets, when in reality most people have niche needs. It's just that there are many niches. E.g. I know people from scientific circles who use CAS software I've never even heard of, my sister is an architect and needs to use CAD software. YouTube video authors often use advanced video editing software. Musicians use audio editing software. Publishers use Adobe InDesign. Then there are gamers. This "not geek => mainly spreadsheet user" stereotype is really strange.

And basically everybody, whom I know personally, complains about the UX of anything web-based, so don't even think about putting CAD, CAS or InDesign into the browser.