I donot agree completely.manali is still a hit but kasol has come to the level of manali and became an instant hit for new generation travellers.
Same thing happen with shimla also.it has became a 2 night vacation spot from 5-6 days.
Everyone says Manali is touristy, I dont think so. Try doing non-touristy things. Eating in locals home, explore lanes on foot, buy local handmade items, get to know stories of people there. Tourist is a mindset not a way of experiencing.