For such a pricy car, yes, but other than the door handles, everything seemed to work fine, at least with regards to the interior.
A lot of the problems were software, and the car improved substantially after a big software upgrade. (And after reattaching the big battery. That had been the cause of most of the “doesn’t move” incidents.
There was the funny time that it randomly died on a suburban back road somewhere. It was still under “bumper to bumper” service, so a Ford technician came out to give us a jump start or something. And he said, “can you open the rear door”. “No”, i replied. “I need the rear door open to get at the battery”. “Yes, but i can’t open the rear door without power, and the car has no power. So no, i can’t open the rear door for you.”
He managed to get at what he needed, somehow. But honestly that was a stupid design decision.
Anyway, the other reason we traded it in was that we got rid of our van, and the c-max didn’t have enough cargo space for a long trip. We debated getting another hybrid electric, but at the time, they all had worse cargo than the c-max. Yes, we could have rented a car for the two trips annually where we would have needed that. But i thought about how stressful it is to prepare for those trips, trying to fit everything in around work, and decided that the extra time and stress of also dealing with a rental would be really unpleasant. So we got a Subaru Forester. I miss a lot of the bells and whistles of the c-max. (It had awesome automatic windshield wipers, for instance.) And we’ve upgraded the power in the house, so we can now get (and charge) a fully electric car for our next vehicle.
Anyway, to answer the op, i think plugin hybrids will be a useful option for another decade, at least, and if there’s one you like, i wouldn’t avoid it for being “dead end technology”. Our next car will be fully electric because we have two cars, and can use the Subaru for road trips. But if we had one car, I’d still be looking for plugin hybrids.