Thats what I wrote.Take individual fouls out of context why don't you. Zinchenko was booked because if he hadn't fouled Villa would have had a goal scoring opportunity.
Arsenal were very lucky they didn't get another 2 or 3 yellow cards for similar fouls that went unpunished.
City instantly get yellows for this sort of foul - if Arsenal don't then referees are being inconsistent.
(I know they are inconsistent BTW)
No consistency. Havertz not carded for a deliberate jersey pull at the edge of the box.