I don’t think Johnson, Kasdan, Abrams and co. even remember or care about a character who only exists because of a single mention in the PT.
That doesn’t mean they still couldn’t make him Plagueis. We all know that Lucas didn’t intend on having Luke and Leia being related at first but it still happened. There are those who even say the “No, I am your father” twist wasn’t there since the genesis of Star Wars. So why does that invalidate the possibility that they could make Snoke Plagueis even if they didn’t originally have that in mind?