In our case, we're not using a text editor, but instead building a spreadsheet, so a lot of these collab-built-into-an-editor are, like you say, pedagogically useful but less helpful as direct building blocks that we can just pull in and use. But the advice is very useful, thank you!
Interesting! I am building a spreadsheet and the next few months will be building the collaborative side of it. I think many of the things that work for text don't necessarily translate for spreadsheets.