Charter schools are definitely a thing in the states, but the objection to them here is that they take funding, good teachers (the pay isn't shit), and good students (because funding is tied to test scores, and the easiest way to get the extra funding is to recruit the students who will score well regardless) away from the public schools. I went to one, almost all my teachers had PhDs in their subject, most of the people I graduated with are solidly professional middle class now... but we were the only school with a full time librarian, lab equipment in our science classes, and computers that weren't Apple IIs or PDP-11s inherited from a community college in a school district with a graduation rate around 60%.
In Sweden charter schools consistently pay their teachers less. Charter schools here are also often accused of inflating grades of their students, because that will attract more students/give the illusion of a higher quality education. Which makes me think that the rules and regulations around charter schools in the US and Sweden are probably quite different. Things like these can make reading US/English news a bit confusing sometimes, because whilst it is the same word the context around it is obviously different.