I don't think it was a swipe at minimum wage employees at all, more massive corporations like Burger King making their minumum wage employees be "cheerful"

One of many reasons I despise Trash-Fil-A. They go hard on forcing their employees to sound a certain way, and it's just creepy as well as being abuse of their workers.

Paying someone a pittance, or anything at all, doesn't entitle you to control over their perceived mood or how they speak. You'll have to negotiate with SAG-AFTRA if you want to hire actors.

But elsewhere in the article they show that Burger King is using AI to analyze how well the drive-through employees are doing and if they’re being cheerful enough and such.

So I think it’s more a jab at corporate mandated performative forced happiness for customers then the employees themselves.

Sure, could have written "hapless Burger King employee…". I suspect they did not realize it might come across the way it did to some.