Why did GM quit making 2wd Blazer in 1982

[justcuz]

Same reason the newer body style Blazer 92-95 lost out to the Tahoe. Sales, pure and simple.
If GM could sell enough of them to justify production, they would still be making them. However the convenience of 4 doors on just a 9" longer wheelbase (108/117) converted the market.
Same story with the Bronco/Expedition.
I had heard that after selling 250,000 vehicles the development cost of a vehicle was paid for. The rest was materials, labor and profit.
So 2wd Blazers did not sell well enough to cover the costs of manufacturing them.
Too bad too, because here in Southern California they were coveted as pre-runners by the desert crowd. I have 3 friends that owned them.