I'm still (a bit) undecided.
I've seen some interesting alternatives on YouTube and in this forum. When I tour with my wife we will mostly stay in B&Bs, hotels and the like so no RTT is required. But if you find a nice spot (you know, like in all those overlanding videos, where you hear the gentle sound of the sea at night and a friendly, light breeze caresses the tent, and your partner wakes you up at the most beautiful sunrise with hot Coffee ...
), it would be a shame not to have had such a great experience because you ended up in the breakfast room of a B&B.
But if you have to carry around an RTT for 20,000 kilometers to experience this unique, wonderful moment once in your life, then it's like playing the lottery for 50 years to win $100 at the end.
I am convinced that in such a tent you can relax wonderfully in the shade of a tree and the beach is only 100 meters away. But at the latest when you have to get rid of the daily morning shit, the romance is over.
Another disadvantage is the noise when driving - and the additional fuel consumption, not to mention the raised center of gravity.
If I/we were overlanders traveling to a continent lacking infrastructure and thus planning options, an RTT would certainly be of great help. But I'm afraid I've seen too many YT videos like this: Such equipment is almost never necessary when traveling through Europe, at least not if there are only two of you.
As a compromise and in case you simply have no other choice or just want to reminisce about past adventures or immerse yourself in nature as much as possible, a sleeping place inside the car seems to be the right choice.