I like him. He's a decent shot stopper, nothing more, but he has an aura that good goalies have. He's become far more proactive in his approach, claiming crosses and more willing to sweep in behind the defense. He's also cut out his brainfart mistakes, as we knew would happen as he settled into the team. He's also had to endure playing with a different defense pretty much every game, so that makes it hard for him as well. He's been one of our best performers over the last couple of months, and yesterday he had another good display.
However, I do think that it is possible to prevent all three goals yesterday. The MacAllister goal is definitely a goal that the best goalies would be annoyed with - a prime DDG, Courtois, Allisson, Neuer, Ter Stegen, etc would most likely save that, deflection or not - it's a long way out in his corner.
The rebound off of Nunes' goal is also rather poor - a goalie should deflect shots where he wants it to go - over the bar would be the best bet there, or out wide. Again, something I'm sure he's annoyed with.
I also think the third shot was possible to save - again a deflection, but he actually does get his hand to it, which shows that it's not impossible - it wasn't that far from his original position. Onana struggles with low shots; we've seen that all season. He has a strange technique where he goes up before he goes to ground - that takes more time than going low as the best shot stoppers do.
None of the goals are mistakes at all, but I do feel that the very best shot stoppers could prevent all three. Then again, Rashford missing a sitter, McTominay shooting straight at the goalie are FAR bigger mistakes than anything Onana did (the goals weren't mistakes per se).