He was awful on that disallowed goal, really think it was Solanke looking at Raya and not the ball, rather than the extent of the contact itself, that led VAR to confirm the foul. I like Raya, and I think Arteta bought him because he lost trust in Ramsdale's mentality (likely stuff behind the scenes), rather than because he saw Raya as this incredible talent upgrade. But he hasn't solidified the #1 position yet.
I do trust that he will continue to improve though. He doesn't yet have that assurance and mad confidence you want from a keeper, and that's been exposed recently, but he has a good head on his shoulders.