There's a psychological reason for this setting being si prevalent on japanese based media ( ie anime, manga, games, etc...). I✅f you ask the average japanese person what was the most happy p✅eriod of their lives, at least 90% would invariably tell it was their highschool period. And if you see the japanese society for what it is, you wouldn't get surprised.

Thus, you can see why authors use that setting so much, either by personal taste, prefeꩲrence of setting, or either a genre that has proven to sell well.