Came in to male this point but you beat me to it. Sterling has had a fantastic season. Scored lots of goals, lots of them important. Against the backdrop of a fan base that largely hates him for reasons we won’t get into and the signing of Bernardo. I don’t think many predicted him to be where he is today and it’s great testament to him. Plus as mentioned the fact he’s been around forever counts against him when it comes to “young” awards - people like the new and fresh.
Sané though, while not as consistent as Sterling, has reached considerably higher highs this year. Occasionally turns in best-forward-player-in-the world-not-named-Messi performances, and is just an incredibly complete player already. Passing, movement (tho not as good as Sterling), finishing, chance creation etc are already right up there. Not forgetting the devastating pace. The plan with him in the side this year is to have him touching chalk, but with Mendy I’d imagine you see him drift inside a lot more next season and add more goals to his name.
He deserves the award.