Verizon (which is Engadget's parent company) and T-Mobile have also criticized AT&T's move. It remains to be seen whether AT&T will face more serious blowback -- the FCC is currently out of commission due to the partial government shutdown. Still, it's clear the company's rivals are not standing for it trying to pull the wool over customers' eyes.

"Sprint will launch and market real 5G that is standards-based in the first half of 2019," Sprint said in its statement. "We're designing our mobile 5G footprint at launch to cover the downtown metro areas of 9 top cities, with sights on providing our customers with contiguous coverage using the first 5G smartphone in the US."