They are absolutely 100% real in New York City still, and growing up in the Midwest they were real.
Yeah, I haven't travelled much in the past few years, but I am thinking about it, and I think they are pretty common all over the US, or at least the eastern part.
I live in Toronto, and the Chinese restaurants which still have the wonton font here are a dying breed. They're American-Chinese / Canadian-Chinese food which I'm usually not particularly fond of, and they are often not very good quality either (at least around here). Toronto has a large Asian population and the better quality restaurants frequented by Asians would not have the wonton font. They're either newer restaurants that appeared after the influx of more wealthy Asian immigrants in the 1980s/1990s/2000s, or else they are restaurants that have undergone makeovers to compete.
BTW, I decided to look up wonton font just now, and came across this article. In there were some interesting points, including from Apple's previous lead typographer. I don't want to get into political discussion here but it I think it does illustrate how this font has lost its popularity.
If the food is better, I can understand to one type of place over another, but you never know unless you try them.
Stereotyping a restaurant based off of the font they use wouldn't be the best way of determining the quality of their food, imo, and you might missing out.
As for the font, people can look at just about anything and say it is racist in some way due to something in history. It really takes the teeth out of the word. I think intent is everything.
Also, maybe look at who the font is bothering, probably mostly white people. Asian-owned restaurants are using it.
Saying that one likes to eat where the asians like to eat might worse than a font, as it is stereotyping people. It still doesn't bother me though, maybe I am not a sensitive as others, as I think intent is important.
This kind of reminds me of the people that say Hello Kitty is racist because it is a metaphor for delicate and submissive Japanese women. Sometimes, it is just a little much and people just need to relax and enjoy life, imo.
So it seems that this was already a meme 3 years ago.
Probably like many other tropes, stuff like that adds the Americana vibe in movies. Other things like this are cheeseburgers, hotdogs, cookouts, French fries, baseball, football, large green lawns, big cars, white picket fences, those red solo cups that you already mentioned, etc.