I live in RSA but toured Morocco and Europe in 2017 for 5 months with a RTT on a Landy Def 90.
For overlanding it is the ease of setup and tear down. Within 5-10 minutes I can have my camp set up completely; tent up, bed made, table out, chairs out, and drink in hand. Also I feel somewhat safer being off the ground...in Africa there are may creatures that can do you harm.
There are cons; the early morning pee can be a mission particularly when it's multiples. The other down side is that you must pack the RTT if you want to use the vehicle to game drive or pop out for supplies. If you are planning to camp in one spot for a week or two the the collapsing of the tent is a pain. We never stay long in one spot so not an issue.
There is an age related 'con'. While young and strong the climb up the ladder is not worth thinking about but when you are in your later years that climb can become Everest in size, particularly for the ladies. Then there is the decent in the morning. There is no gracious way to reach the first step of the ladder without mooning the camp.
All in all, I like the RTT.