That’s not correct. Some of the top-rated public schools in the country are in PA. Note, for example, that people working in Delaware like to live just across the line to get their kids in PA school districts.
There are terrible problems with PA public schools, but those problems are widespread.
People are moving from Pa. to Delaware not vice-versa. And some of those highly rated public schools on the Delaware border (i.e. Garnet Valley) are highly over-rated.