I tent camped for many decades. In contrast to what practically everyone here has said, I like those car top popup tents. I wish I had one back in the 1990s and early 2000s when I had my Cherokees. It would have made a great combination, 4x4 to get way back into wilderness places, and MINUS the hassles of putting up the regular tent.
My dome tents would take 1/2 hour or so to setup and about the same to put away: ground cloth, tent setup, move padding and sleeping bags and other stuff from the car to the tent. And the worst part is, tents are a horror to pack up when wet.
OTOH, some of the popup tents can be erected and taken down in a just few seconds. Plus the padding and sleeping bags can stay in the tent. 3 years ago, I met a couple with a dog in Death Valley who had a rather small Honda Element with a popup tent, and they loved it. If you can park near some trees, then you have some shelter from high winds, and if "really" strong winds do come up, you can drop the popup in a few seconds and sleep in the car. Try taking down a regular tent in a heavy storm. It sucks. And there is another big advantage over a regular tent that is soggy and wet. With the popup you park, flip it up, and let it dry out.
I have a van now, but if I had just a regular car or SUV, I would strongly favor the popup tent over a regular ground tent ... any day of the week, and twice on Sunday.