Changed the artist name, it has to be Yoh Yoshinari and his collegue just misspelled the first name. It’s the same style as Yoshinari’s other pony fanart and they work together on Studio Trigger.

@BigMax
 
Yoh Yoshinari is a well known Japanese animator and character designer who worked at Gainax (you can check out his work in Evangelion,Panty and Stocking with Garterbelt,FLCL,Gurren Laggan and his most recent Little witch Academia).
 
He’s also known for being a western cartoon enthusiast.If you check out his Pixiv account you can see his various fanarts of cartoons like The Powerpuff Girls and My Life as a Teenage Robot.Heck,he even knows about The Galaxy Girls as he made fanart of Pluto (the Rocker girl).
 
He’s not dead (thank God) what happens is that the OP most likely said that because he already caught the Pony Bug.I mean obviously,what with the show airing in Japan was something hard to miss hahaha.
 
here’s an example of his fanarts:
 

 
@Background Pony
 
lol.

I don’t know who this You Yoshinari is, but according to Wikipedia he’s not dead.

Time to make this a little creepy:  
“Come and stay with us. You’ll enjoy staying in Equestria and being a pony with us…. Forever….”