The difference is when Allison was fouled your player was competing for the ball and made a movement toward Allison.
Ben White for instance, would know where the ball is going to be played, and he will literally plant himself in an area that blocks the keeper's pathway to the ball. In a literal sense, all he is doing it standing rooted to a spot. White literally just stands rooted to the spot like a pot plant. There is no 'literal' foul.
Another thing, is we also have to defender corners, and Raya doesn't seem to get locked in like other keepers. Infact Raya often comes to claim the ball.
My honest assessment. Were a big team, we have an absolute number of units in the team at any given time. The average height and weight of the Arsenal team on majority of occasions would be taller/heavier than our opponents. Were not fouling teams, were just out muscling and out jumping them. Everyone got so used to the idea Arsenal are a soft touch, a cliche from the days of Wenger when we used to stack nimble nifty attacking midfielders like Nasri, Cesc, Cazorla, Arshavin, Rosicky, Hleb ect. Teams had a lot of fun bullying Arsenal. Bolton, Blackburn and Stoke especially. Now though, its Arsenal that are doing the bullying and our rivals dont like it.