Not to cope with this but for me it was more that I was smart enough as a kid to coast through school without putting in any effort, not paying attention in class, not taking notes, not revising and often not even doing homework and just getting good marks on exams from knowing things already or just applying some logic to the questions and because the school system only cares about getting as many kids as possible a passing grade, the school didn't care and just left people like me to our own devices and focused all the resources on the kids that were failing. Then when I got to A levels/ uni, where things suddenly got way more difficult, I just hadn't developed and of the skills to actually learn stuff like that and I floundered (and I'm sure having ADHD didn't help).
So for me at least it was less about burnout and more about my "natural smarts" only taking me so far and the school system failing me (and me also failing myself)