> example: my parents taught me maths, my grandmother taught me how to read and write, I learned English, Lua, C, etc... on my own, learned physics and chemistry by reading books

Which proves only one point: that you had the advantage of an extremely interested, caring and knowledgeable family.

Many people, especially PoC and "poor people", do not have this advantage (be it because parents or other family are locked up in jails, or because parents have to both work two jobs in order to make rent) - public schools are the only education resource for kids in these families. We as a society must not let them down or we will face the harsh consequences in the future.