Please. I'm not one to defend Portnoy, but if you don't think this is people having something against him I don't know what to tell you.
I don't have anything against him. He does what he has to do for Dream Theater. And he's a brilliant drummer.
But outside of DT, with musicians like Michael Akerfeldt and Steven Wilson (better musicians who offer far more range in their work) - he's just not needed as a creative influence.
I'd like to hear him on the drums as well, but there's loads of top class drummers out there. Is there loads of song writers like Wilson and Akerfeldt? Absolutely not.
Simply put, he isn't needed.