Lol

I think they mentioned his declining mental health.

They never explained Ash's different appearance. Ever since Sinnoh Ash has had a facelift every region. Honestly, Ash's appearance changed over a freaking plane ride from BW to XY (albeit a more minor one than the one we have right now), so I don't think they would ever explain that.

It's a children's cartoon.

Does it matter?? If the game is anything to go by Sun and Moon's anime is aimed at the Yokai Watch crowd. Whilst I haven't seen the XY anime it sounds like S&M may be quite different.

I don't like the anorexic version of pikachu, so I probably don't like the new ash either

Its a prequel.










Its not.

I think that due to this style change the Pokémon Anime can now be confirmed 100% dead, the art style was one of the few things that were good in it, now it just looks like a western cheap cartoon, I mean the Pokémon look better on the 240p screen of the 3DS ff's sake...

Its just a style change. Inside the Pokemon world Ash looks as he always has. Think DBZ, Toriyama's art changed significantly throughout series. When Goku has a flashback about the tournament where he fought Jackie Chun, its done with the Buu Saga art style vs what he drew like during Dragon Ball.