The live action Death Note was pretty well-acclaimed, though that's an anime that takes place in the real world, stars ordinary people, contains nothing supernatural except the shinigami and the Death Notes, and is very talky. But I'm just using that as an example to say that it's possible to make a good live-action adaptation of an anime.
Pokémon would be way harder than Death Note, obviously. On the other hand, The Dark Knight is still at #1 on IMDb, meaning people absolutely adore it. And this is a movie about a billionaire who puts on a bat suit and beats up criminals.
A good Pokémon live-action adaptation would definitely be possible, but it would probably have to take a similar approach to what Christopher Nolan did and redesign everything from the ground up so that it CAN make for a compelling story. There are just two problems with this: Pokémon is a hugely successful franchise, and thus, you don't need a lot of effort to produce something that'll make money. Secondly, Nintendo would never allow anything too offensive or controversial to show up in a Pokémon movie, which would simply be impossible when your concept is superpowered cockfighting.
I wouldn't like it live-action anyway. I don't see what the big fuss is about having to do everything live-action.