You don't have to, I've seen all the games. I know Ederson has been good but not great.
Just because you make risky outbursts and play it cool from the back doesn't automatically make you the greatest keeper.
And to my point, once we actually lose possesion of the ball and the other team has maybe 1 or 2 attacks all 90 minutes, we concede. That is the problem.
Considering how few chances the other team gets during 90 minutes, we should count on him to save a few. What kind of keeper is he if Leicester has three chances all game and he lets them all in? You could might as well put Sané in the goal.
And seriously, we have to be able to criticize our players when they are not playing well.