If everyone sent kids to private schools the public school system would collapse.
If we saw even half of public school students go to private or home schooling, then the number of teachers and schools needed would likewise need to shrink. I can’t imagine that the same level of funding would go to public schools, if they didn’t have anywhere near today’s enrollment.
Tax money would not go to the schools in the amounts it does now, and we would see teachers laid off.
I’m not familiar with details of private school operations, however, I can imagine that there is far less bureaucracy or need to deal with politically correct dogmas in the curriculum. There would be no need to teach about “LGBT” issues, if a private school chooses to avoid such subjects.
Already collapsed. Just about.