Depending on the kind of notes you have in mind, there are some much more solid and transparent projects around.
- Observable HQ is excellent, with very distinguished figures like Mike Bostock and Jeremy Ashkenas working on it.
- For more general working notes Notion is solid and I know people who swear by it and live in it.
Personally, though, I have learned to prefer local storage and desktop applications. (I haven’t forgotten losing a rather large amount of work in the 90s, when someone had an unfortunate accident with their server, and seemed to have kept imperfect backups 
)