As an instructional designer, I've noticed an uptick in the issue echoed in this thread - students skipping instructional content and going straight to assignments if they're not otherwise locked-down. I'd like to add in another thing I'm noticing, which is stemming from the facts that the To-Do list sorts oldest-first by default and has a 6-7 item limit before "Show All" appears.
So, if a student is falling behind on 6-7 or more assignments, the To-Do list no longer displays future upcoming assignments and instead shows a backlog of old work. Yes, the student could hit "X" and clear this out, but many don't. Clicking "Show All" doesn't lead to a comprehensive list or link to the student's Calendar, and instead switches the Dashboard over to List View (which, in my personal opinion, is confusing 🙄). As a result, the interface design is appearing to exacerbate a student's late/missing work struggles.
As a teacher, I try to catch my own students before they get this far behind and guide them through assessing whether catching up on all work or taking zeroes and only working on remaining upcoming work is a better choice. This could be a bigger challenge for instructors whose courses are mostly online and/or aren't Canvas admins, though, since there'd be less of an opportunity to take a look at a student's own To-Do List yourself.