The problem is that it is such a pain in the a$$ to bring to market, that it is almost not worth it in a lot of cases. I'll be curious to see how the mini-max sales do in the long-ish term; the diesel Cruze was killed off in 5 short model years.
Large displacement NA V8s are returning to the truck segment because diesel is so costly in ownership.
Hyundai and Mazda were both slated to bring small diesel SUVs to the
but the effort to certify meant they eventually killed them off shortly after I left Bosch.
I do not have high hopes (long term) for diesel in the light duty segment.