To be honest with you, I don't know why people say that Wish is better than Moonlight. Wish restores 1/2 of the maximum HP at the end of the next turn. It works even if the user has switched out. Moonlight recovers 1/2 of the users maximum HP in normal weather conditions. It recovers 2/3 of the users maximum HP in sunny or extremely harsh sunlight weather conditions; and it recovers 1/4 of the user's maximum HP in a rain or heavy rain, sandstorm, and/or hail weather conditions. Either way, both, Wish and Moonlight recover 50% of the user's maximum health in a normal outing. I'm also not one for switching in and out a thousand times, so when my friend's and I battle in person, we go pound-for-pound with little to no switching Pokemon in or out. So, a lot of our group are built with coverage moves, making a move like Wish vs. Moonlight, only different in that Moonlight is instant. Keep in mind that Pokémon battling is about strategy, so trainers setting up for Wish or switching out with it can be part of a strategy.