Diesels caught on in Europe because primarily of good fuel economy. Fuel is expensive in these parts of the world, and Europeans tend to drive smaller cars with smaller engines because of that. In the "old days" diesel cars were frugal and cheaper to run, but they were also sluggish and not very refined. When modern and efficient diesel-cars started to come out on the market, people turned to them as they were not only cheap to run, but also much more refined than earlier. A modern turbodiesel were more powerful than a comparable gasoline car, so that played a part too.
The main problem with diesel, aside of Dieselgate, is that modern diesel-engines do not like frequently short trips and subsequently clogs up. Particulate filters, injectors, turbos - yep, a lot of things that can go wrong. And they do. For longer trips - sure, they work fine. But many lives in urban areas and only do short distances for the most part. The engine doesn't heat up properly and stuff starts to happen from there. What you save in fuel costs, may well be lost in what you have to spend in maintenance costs.
Then you also had higher emissions of NOX and particulates. This became a fairly big problem in urban areas with a lot of traffic and there has been attempts from local authorities to try to reduce these.
People have generally become more aware too, and evaluate their car needs more than before. They just don't look at the low fuel consumption of a diesel-car, but also see if their driving pattern is suitable for a diesel-car.
Toyota have also been advertising hard for their "self-charging" hybrids. No need to plug in - they charge themselves magically!
My parents bought a RAV4 Hybrid in 2016 and they were looking at the Outlander PHEV as well. The Toyota-salesperson flat out told them that the Outlander could not work as a regular hybrid. You had to charge the battery at home, and when it was empty, the car would only be able to work as a regular ICE. It could not recharge while driving. My parents still bought the Toyota after I told them that this wasn't true (there was other reasons to why they prefered the Toyota). They are not that pleased with its fuel consumption and feel it is a bit thirsty, especially when comparing it to my Subaru Forester diesel (which is similar in size).