Are CVTs as reliable as traditional automatic? Why do so many new cars have them?

I'm about to get a new car and the ones I want all have CVT transmission (Honda, Nissan). I don't know why they don't include an automatic option. Specifically I'm interested in the Murano. I heard Nissan CVTs aren't as good as Hondas?

I tend to drive my car 200k miles and keep them for 20 years so I need to make sure CVTs can last that long.

CVTs score a point or two more on the MPG derby, which explains their ubiquity.

Given typical owner maintenance, which is to say none, most ordinary automatics don't make it to 200k. (Hondas of a certain age have an appalling failure rate.) CVTs require a little more attention than normal *and* a CVT-specific fluid.

They are supposed to be more reliable and get better mileage than a regular automatic. They can be shifted like a manual transmission but no clutch to deal with.