That's kind of the point, though--you don't have to do x, y and/or z. It gets better instantly, the day you graduate, simply by virtue of not being trapped in a high school building with sadists anymore. Sure, you still have to get a job and live your life, and in a small-town blue-collar scenario you are likely to encounter a lot of the same types of people you saw in high school. But the difference is, most behavior perpetrated by high school bullies--vandalism, harassment, threats, assault--is at best a firing offense and at worst a prosecutable crime, when it's done out in the real world. Not to mention, you now have the freedom to move to a larger city if your small town is an exact replica of the high school environment. You can hitchhike if you have to, and your parents can't say anything about it, whereas before they could have had cops haul you back as a runaway.
I disagree that it automatically gets better. My freshman year I had a roommate who had a lot of troubles in high school. I don't know the full story but he switched schools between his sophomore and junior years of high school because of bullying, isolation, etc, and supposedly the school he went to junior and senior year wasn't much better. He said he was suicidal for a while as well (honestly I thought he was looking for attention at the time but whatever).
Anyways, so we met the summer before freshman year of college through some roommate search and he was extremely excited for a new start and to be in a much more "mature" environment. He had plans of meeting a bunch of people who weren't judging and all of that stuff.
But one thing we both didn't realize at the time was that people are going to judge you on how you act no matter what. There isn't some instant rush of maturity that occurs when someone leaves high school. The same people we were hanging out with freshman year all graduated high school the year before. If you were bullied in high school there was usually a reason for it, some more legitimate than others, and acting the same way when you graduate will most likely result in people treating you the same (being gay can be somewhat exempted from that but I'll get back to it).
So I quickly found out that this guy was creepy and weird as hell and tried way too hard to impress people. This naturally turned all of our hallway against him and he went back to the same old trends as he did in high school. I haven't talked to him since the end of freshman year but unless he changed how he acted, I bet he still gets treated the same way. It may not be as direct as in high school or the dorms, but it will still happen.
I had another old roommate, junior year, who had an opposite situation. He was king back in high school. Star football player, second best wrestler in the state for his weight class, valedictorian, popular as hell, etc. He lived in a small town and when he moved to the University of Minnesota he eventually found out he was only average compared to everyone else. There were other issues too but I could easily tell that this bothered him because he would get very insecure and call himself a "genius" and talk about how great he was back in high school. He became an alcoholic and has nothing to show for himself right now. I know a few other people that have the same basic story but just not to that extreme. All of them live in the past.
While I do agree that graduating high school for the most part gives everyone an opportunity to live a better life, I would never say that it automatically gets better. People are going to be judging and be assholes wherever you go. A lot of people are miserable and that is apparent of how they treat other people. Almost all my gay friends are much happier now than in high school because they stopped giving a shit what other people think about them. Getting out of their high school helped A LOT, but it still came down to getting rid of the insecurities instilled on them for the past 12 years.
Graduating from high school gives you an opportunity to change but you still have to do it if you want to be happier.