I don't think there is any revisionism going on. You have stated yourself that last season wasn't his best and then he has carried that lack of form into this season. Last season he got 30+ goals which for me, makes up for his poor performances overall. I wont knock anyone who bags 30 goals a season. This season however, his poor performances have continued (arguably even worse) and he isn't scoring the goals to cover for it. That is a problem.
What worries me is that in his early days at the club he was poor, which mirrored the team as a whole. Then as the team got infinitely better in 17/18 and 18/19, so did he and he looked genuinely world-class, in what was arguably the best front 3 on the planet. Then as the team has regressed since the beginning of 19/20, so has he. The very best players produce even when the teammates around them aren't. We have a prime example in KDB winning POTY even though the team as whole weren't at it. If Sterling needs the team to be firing on all cylinders for him to show up, he isn't world-class.
He either needs to step up to the plate and show everyone that he is a top player, or he needs to at least start scoring again. If he does neither, which is where he is at the moment, he is of no use to us whatsoever.