You can quit a crappy job. You can transfer to a different university. You can ghost your friends. In nearly every social system after high school, there is some measure of self selection. But you have no power to extract yourself from that environment unless your parents are willing to send you to private school or move.
I am not sure there is a need to abolish high school, but rather just provide additional resolutions for those for whom it is a very poor fit and better clamp down on those who want to harm others in the ecosystem. Schools handle edge cases very poorly and they do an even worse job of managing those who wish to do harm.
[0] http://www.psychological-observations.com/918-jmh-internatio...