Thanks for the answers, guys! Setec that makes a lot of sense, if I want the just waxed look, I have to wax the car often!! I'm not quite ready for a coating yet, but surely will be one day!
A thing to note is how incredibly clean cars seem to stay, on which I've used Opti-Seal or Car wax on and how easy they are to clean. I've noticed this on several cars now.
I've gotten the feeling that other brands use certain substances that, while they give great beading and sheeting, don't have the same self cleaning properties. Like I said, it's a feeling, so I hope to test that out soon.
Most notably has been the Tesla of a neighbour on which I did a wash an wax (drying aid, too sparingly; one spray per panel). It had gotten very dirty again a couple days later, but it cleaned itself very well. So much so I was convinced they had washed it themselves, but they assured me they didn't . There hadn't been any big rainstorms either! Astonishing.