This same thing happens over and over.
GM will bring out a diesel and in a couple of years they discontinue it.
Only the full size pickup has enough sales to justify keeping them in production.
Personally, I don't think that GM makes much of an effort marketing their diesels. They when they cancel them, the party-line is that they cancelled them due to slow sales. I's have to call BS on that one !
2018 Equinox LT1 1.5 L 4 cyl, AWD, S/R Cajun Red Tintcoat/Black
2010 Equinox LTZ 2.4 L 4 cyl, FWD, S/R Cardinal Red/Black