Call me when there’s a serious OneNote...

OneNote works on the web, but there's also Notenook if someone is looking for similar features with an app for offline access + End-to-end encryption and open source alternative. I've got it syncing to my Android, Windows, Linux and Mac clients without issue.

...or even more importantly, Excel competitor.

There's OnlyOffice which has a spreadsheet. Yeah it's not Excel which has existed for a million years, but it should work for the vast majority of users' basic needs. It may not work for your specific use case, but it is a viable alternative that exists today. If you want more online collaborative features (like the o365 version has) you can use CryptPad, which provides an end-to-end encrypted and open-source collaboration suite, including the web version of OnlyOffice Spreadsheets.

Or even a standard shell on Linux...

What does this even mean? Nearly every major Linux distro sets bash as the default shell, and if not the default, is probably already installed and called if needed. Not sure I understand the problem here.

...or the same set of tools built in

Stick to a single OS and you get the same set of tools built in? This is a strange statement to be making against a system that not only thrives on diversity but has lots of niche systems that require a myriad of default tools.

I do completely agree about not using any browser's built-in password manager.