No-the CVT alone is not their downfall. If you spent anytime in a Nissan Dealership-you would know their downfall. The quality of their dealerships and sales leave ALOT TO BE DESIRED.
I drove a 2006 Sentra for 11 years, then handed it down to my kid, who drove it through college. It was a good car. The local Nissan dealer was good. Maybe just luck, to have a good dealership close. Next, I bought a new 2017 Civic. Again good car, other than the AC system. The Honda dealer, just a couple stores down from Nissan, in the local auto mall, sucks. They jacked me on AC repair. Only way I'll ever go back is if any recalls pop up.