I definitely agree on the distinction between the "todos". However I do find that I need to see it all in one place for me to function. Even reminders and tasks have dates and times that interfere with calendar appointments. Still looking for an app that integrates everything flawlessly. Right now I'm using ticktick for tasks (and can see my calendar with the tasks at least). Reminders I do on Google calendar (through smart speakers mainly). Works pretty well.