If you really do care about education and want to make a difference, then well....become a qualified teacher! Nobody should expect to be hired as a doctor without going to medical school, likewise nobody should expect to obtain a serious teaching position without proper certification.
Then once you do get certified, you can work for an international school or bilingual school where you are taken seriously as a teacher, and your results do matter. The parents at these schools are paying ridiculous sums of money to ensure their kids become proficient in English, and they expect results.
Your students will sit standardized exams (ex. IGCSE) and your HOD and school director will expect results. You will have reasonable class sizes, decent resources. Not only will you have the opportunity to shine as a teacher, you will be expected to do so. Sure, that means more work and more stress, but you will be making a difference (at least, for the kids who can afford your school's fees).
Thai government schools are a great place to be for "teachers" who aren't qualified and don't care. They just want to be in Thailand, live a stress-free life, and do a joke of a job for an okay wage. And that's great for some people - those who would otherwise be working at McDonald's or stacking shelves in a warehouse in a Western country can come to Thailand, play the role of a foreign "teacher" and live a much better lifestyle with few professional expectations.
But if you find yourself stuck in one of those jobs (most likely due to lack of teacher qualifications) and actually care about teaching, then well... do something about it! Sure you could argue till blue on the face that teaching qualifications might not make you a better teacher, but if you were a parent paying $20,000 USD per year for your kids school, you'd expect certified teachers.
So ask yourself, what kind of teacher do I want to be? And then get the qualifications and the job that allows you to be that kind of teacher.