To me it honestly seems odd that people think a 2nd playthrough would be unbearable; with NG+ options a 2nd playthrough's pretty much a breeze and definitely not another 100 hours.
For those that don't know, after you clear the game once, you keep your compendium, money, and social skill parameters, meaning you can blitz through dungeons, max all social links & focus on completing certain trophies in your free time with little-to-no worry about time-management.
With that in mind, you can just focus on having fun and figuring out things as you go along in your first playthrough without the worry of missing out on anything, or constantly checking a guide to make sure you're doing a certain thing every single time slot, which many usual Persona players agree kind of destroys the fun of the social Sim part of the game.
Of course, people are free to do whatever they want with their game and time, just giving an honest opinion of why going in blind your first time through is a more entertaining experience.