My parents are 60 years old and use mint daily. When my mom needs onedrive she just uses the web app through the internet browser. At this point its better for your boomer parents to move them to a OS where they aren't a product and the corporate overlords won't be able to fuck with their local files. the 99% of normal users only use their computers to boot into the internet browser, and every piece of software they use from banking to documents has a web-based front end, a FOSS alternative, or can be emulated with wine.