School has its uses like you said, but what you're talking about shouldn't 13 fucking years.
Learning things like how to write, read even things like compound interest is great however, when are you gonna need differentiation?
Why do you have to know what Shakespeare meant but this certain stanza?
Why do you need to know happened on a certain day 84 years ago?
Do you need that in daily life? Does the average person really need it?
Sure if you have an interest in it, great, do it, you future career may depend on it all the better, but why should people be forced to learn these things that just aren't useful to their lives and that they'll never use? Why punish a kid for ditching school to hang with their friends because they didn't want to sit in a class to learn a language that they'd never speak. Why are they ridiculed by everybody for flunking a test that asks them to label a plant with weird words they don't see often.
Basic things really can be taught early on, like 6-8 years, you learn so much bullshit in that time that it takes longer to learn actual essential things, maybe then try teaching them actual useful things, like sex ed, taxes, how to vote, money management, how to apply for a job, maybe even survival skills for an emergency. After that, help these little shits find out what they want to do with their life.
Schools should teach more essential information. None of this useless garbage. Also homeschooling exist and while you miss out on social skills not all homeschooled people are untalkative introverts.