His name is right there on the FAQ. He's a media figure, of at least some note, who makes his living predicting political outcomes. If he had changed his stand, he would have the information removed from something bearing his name. It has direct impact on perception about his work.
Disagree; you can't even get to www.fivethirtyeight.com anymore (it redirects to NYT) and Silver is pretty transparent; I think if that affiliation was dependable information, it'd be somewhere in the masthead of his blog.
He'd have it changed.