The trouble with these dealer applied “lifetime” sealants is that they never properly prepare the paint first, they will apply it over poorly washed paint, over scratches and swirls, looks great from 30ft away but not really good enough.
Ceramic coating is the best thing you can do IMO, unless you enjoy applying products to your car, things like glazes, waxes and sealants etc. which many do, and that is the way to go if that is what you like doing, there are tonnes of great products out there for that.
Ceramic coatings give the best protection against washing / drying induced marring and chemical resistance, but aren’t scratch proof like some manufacturers would have you believe, so I still never let anyone else wash my car - although they are typically harder than the paint, usually up to 9H, but still require safe washing methods.
As Boba mentioned above, any ceramic coating does need some maintenance to keep it performing as it should, most of them benefit from “toppers” to help with water spotting issues, to use as a drying aid and finally to act as a sacrificial layer, which will see you reach the full life time expectancy of the coating.
A 6 monthly decontamination will revive and rejuvenate ceramic coatings, by using tar remover and iron fallout remover following a wash.
There are one or two products on the market now which contain iron fallout remover in a shampoo so will perform a mild decontamination each wash, but mostly you will want to use a PH neutral “pure” shampoo which leaves nothing behind, again, tonnes if products out there.
Lifetimes of the different coatings vary quite a lot, and looks can vary also, you can have a candy gloss shine from some, or a warmer wax like glow from others.
Always make sure the paint is at its best before applying s coating, the car should be well washed, fully decontaminated, clayed and then polished - even a brand new car needs this -
A lot of folks are put off by the initial effort but the long term benefits are well worth it.
The paint protection, the sheer ease of washing and drying (especially in winter months when you don’t want to spend a long time doing this but it looks like you did)
A detailer can perform this for you in as little as 2-3 days, prices vary depending where you go. Where are you based?