By Truck Top do you mean one that fits in the bed of a pickup. Some of those are larger than you think but I wouldn't want to full time in one. But there is a forum here for those
Truck Campers (TC). The larger ones require large dual rear wheel pickups. That style of camper is probably best for boondocking and camping in the out country.
Fivers are limited to areas with at the minimum a good dirt road whereas TC can go almost anywhere the truck can go. That's keeping in mind how high the TC is. So yes we sort of miss out on not having a TC but after spending months in a fiver I suspect that the TC would start shrinking fairly quickly. And you give up huge amounts of storage and tankage.
Arctic Fox 25Y Travel Trailer
2018 RAM 2500 6.7L 4WD shortbed
Straightline dual cam hitch
400W Solar with Victron controller
Superbumper