Disk brakes have an advantage in wet conditions and on big descents with a load. Otherwise, a good road caliper is fine. I use both and they are trouble-free.
Disk wheels can be built any rim. Disk rims have no braking surface so can be lighter; they are not stronger . Carbon rims are not famous for effective braking so make sense on Disk wheels.
Disk brakes need a stiffer fork, which is not so comfortable.