Government schools work just fine when they are actually government funded.
I suppose you have a source for that, but just forgot to mention it. But it’s just not true. Too many public school systems absorb wheelbarrows of money and don’t educate students very well. We are pouring inordinate amounts of money into schools, relatively more than we used to, and ending up with a large percentage of kids who are barely literate. No Child Left Behind and Race to the Top were not successes for many disparate reasons, but they both exposed the inconvenient truth that throwing money into public education by itself would do little to raise test scores. Many urban districts are beset with political factions fighting each other. Superintendants come and try to change the system, but soon fall victim to infighting. States come in and try to set things straight from afar, but it seldom works. Outright corruption bleeds money out of many systems and the full extent of the failure to educate students is covered up by cheating schemes orchestrsted by teachers and administrators.
Though hamstrung by incredible bureaucracy and union rules, most teachers try every day to do their best. However, a not inconsiderable percentage just do their time. The number of administrative personnel and personnel not actually teaching has mushroomed. Diversity officers and curriculum advisers keep multiplying. A good part of the blame should be allotted to indifferent or absent parents and to cultural attitudes that disparage education. Meanwhile, children of immigrants from South and East Asia, many who speak English as a second language, go to supposedly underfunded urban public schools and somehow manage to get educated and score well on standardized tests.
School choice puts market forces to work to change the system for the better. Even a bad private school that poor parents can select for their children puts fear into the public school system. But some private and charter are bound to be better. They will siphon off more and more students. We should encourage this, because it means we are getting better educated kids. And if parents want schools that promote their own values, is that such a bad thing?