I haven't noticed any slowdown at all, and it wouldn't depend on the document size anyways. In fact, I remember Docs slowing down on 30-page files a decade ago, whereas now it handles 100 pages just as fast as 1.

Only the visible portion of the document is rendered (previously in HTML, now in Canvas). Everything before/after is just the document data.

Maybe you started working on longer docs coincidentally around the same time Docs switched to canvas?

My “favourite” part about google docs is where if you scroll marginally faster than glacial, large sections of the page just give up and disappear.

You then have to wait for docs glacial performance to catch up and re-render things again.

It’s genuinely garbage and the “live collaboration” features go unused most of the time.