I can only speak for the UK but for quite a while now, McD's has become an uninviting experience, with miserable staff, menu screens that visibly tell you to hurry the f*k up and choose the product. Not to mention customers vying with delivery drivers for orders. I think the problem applies to all-income customers.
"They're poor, they don't care a about basic human dignity." - McDonald's CEO probably. It truly is the most "Shove this in your slop hole you wretch" experience in all of fast food.
McDonald's is laser focused on low income customers. They do not want to compete in the middle income space, as they don't visit as often and there's ton more(and better) competition.
Their CEO has been blunt about this recently, and trying to find ways to get low-income customers back. Dire straits ahead for them, they've priced themselves into a place they don't want to be nor will they be able to succeed in.