That works because Google Docs is a full-screen app. You can't really use Canvas-rendered tables inside a regular web page: it doesn't scale, for one.

I have made a super fast spreadsheet-like component called DataGridXL, based on DOM, not canvas. A performant One Million Cells demo can be found here: https://www.datagridxl.com/demos/one-million-cells

Yeah they sure have the resources available to pull such things off. But for the rest of us I dont think it is a way forward at the moment. You really start from scratch and how do you fix accessibility and such. Must have required huge effort on their part