One thing arduinos don't do is things which require a GPU. So if you have a project which you want to output to a display but you also want it very low powered,

One thing arduinos don't do is things which require a GPU. So if you have a project which you want to output to a display but you also want it very low powered, because it e.g. runs 24/7, a PI is IMO the best device. Something like a Home Assistant dashboard display or a DIY smart mirror for example.