Keep in mind there are a lot more RV'ers who do not or never had a truck camper so naturally you will read more complaints about other types of RVs.
Also keep in mind the folks who post in this and other RV forums do so for the following reasons: they have a problem, they like to help others, they are interested in RVs and what's going on. For the most part folks who are satisfied with their RV will not post on a forum. So when reading RV forums you are seeing just a very small cross section of RV owners.
There are a whole lot more folks who are perfectly satisfied with the RV than not. I'm guessing it's 80 percent are happy and 20 percent are unhappy and of those 20 percent you might see 5 percent posting on this forum.