He is fully entitled to run his contract down, but I suspect many fans are looking at it from the point of view of the club and not the individual.
As we are led to believe, he has had a contract extension offer now for some time, but as far as we know, is remaining uncommitted. Therefore, and understandable, fans are looking at the options, one of which being try to offload him this summer and bring in a replacement now.
I think a lot of the criticism and praise for that matter does go too far at times, but I'm sure Sterling is not fazed by anything written on an internet forum.