.....
The ceramic coating seem to be the dogs danglies, and is widely used by various established Youtubers such as LegitStreetCars... But the prerequisite is that the car is spotless first, so washed, clayed, polished and waxed first.
......
I agree, great results when done properly.

My car is ceramic coated (from new so paintwork good), with a certificated guarantee, whatever that means.

Proper prep is essential, as Al said above, as the ceramic coat is the sacrificial layer between the elements thrown at it and the shiny paint. Any swirls or scratches will be locked in by the coating.
Does it stay cleaner for longer..... no, of course it doesn't.... it just appears to look cleaner for longer as it's still shiny under the road grime. Although in saying that, if it's dirty when it rains it does seem to wash the dirt off a bit due to the coating.

Does it still pick up light scratches ...... of course it does .... it's a coating, not a glass film.
Is it easier to wash each time ...... yes and no ..... my car is Mythos Black so when clean it looks great, but drying properly is so important. As soon as it's rinsed off you need to dry it panel by panel to avoid watermarks. As mine is black it shows any water spot that has been allowed to dry naturally. This means that in warm weather you will dry the car all over, but then have to re-wet each panel at a time from a water spray bottle and microfibre towel it off.
Beading when it rains is impressive though.

When clean, it does look like it has a layer of glass over the paint and looks great.

Would I have it done again on another car .... hmm... that's a tough one ... possibly, but not at a dealership as they can't dedicate the professionalism of a dedicated detailer. It looks fantastic but I never minded polishing my car. My son used to do detailing as his job so I have all the gear in my garage still, so I could do it myself next time. Incidentally, I didn't pay to have mine coated. Figures were juggled to make it appear as if I had. Sales tactics for commission of extras.
