In my case: I don’t have that many TODOs. For instance, I clean home twice per week, on Mondays and Thursdays. Don’t need to write it down anywhere. I have perhaps 2 or 3 doctor appointments per year (and they are usually within a few weeks in advance, so easy to remember). I don’t have kids (this one could be the game changer, I admit).
Work-wise: sure, I have everything in the work calendar. But i have separate laptops for work and personal life. I never mix them.
If we want to go out for dinner, we just go. Cinema? We just go as well. No appointments. I do exercise at home. We usually travel around 2 times per year (again, not easy to miss)