I also just lost my brakes on 2019 Silverado RST on 9/20/2019. Luckily just pulling out gas station. I was able to drive it to the dealer but no power to brakes, had to press super hard to stop and even then was not fast. Quickly after GM sent a text message about servicing my ABS and the check engine light came on about servicing the ABS and not driving over 65mph. Dealer said two recalls on file and one was brake related, go figure. Very disappointing. Then I get a loaner and they say I can’t tow my boat with it to go fishing over the weekend, wtf. Might have to rethink my next truck manufacturer.
Update: Bought my truck December 2018 and has around 7K miles.