I feel your pain. I had similar problems with my 2020 Blazer. The cameras went out and after the dealer had the blazer for almost ten days, they fixed it and they also had to put in a new video processing unit. Then the Blazer was leaking coolant. Brought it back and after three days it was repaired. Soon after, it started leaking again. After ordering more parts and about ten days later, I got the Blazer back. So far, (cross my fingers) it has been working. But all of this occurred while it was under 5 months old and with less than 1200 miles. I feel like you, this will be the last GM vehicle for me too. I hope we both have better luck without any further problems.IDK, asking if I want to sell my 14 month old, 46k vehicle for 5k felt like salt in a wound.
As you can imagine my Blazer purchase is a sore subject, that I regret. I wanted reliable transportation and I spent a huge sum of money for me, on what I thought would be a trouble free vehicle. It has been anything but, and I have had to make arrangements for time off with my employer to bring it to the dealer for repair, burning vacation days.
In total 15 days at the dealer and a new vehicle that has been torn apart several times. They took apart both doors, dash, & console, left/forgot a screw I found on the floor mat, missing panel fasteners under dash panel fell down while driving, they broke the glass of my passenger side mirror while diagnosing camera failure, now passenger door rattles, they scratched my interior door handle, etc..
I thought buying the year after the introduction of the model would help also, but I have talked to 2019 & 2020 owners and I think the problems are surfacing in both years. Batteries, rattles, and electronic issues are the most common (per service advisor & on here).
As for pickups, I had a 2006 Silverado that gave my zero trouble for 13 years, just standard maintenance (brakes & a battery).
My advise, stay away from these vehicles until they work the bugs out, maybe by year 4 or 5.