I think they were, they'd become a wildly inconsistent team imo, regularly getting dingdonged by Brighton et al.
I think Ange came into a better setup than Arteta did, solid defence, reliable midfield, two really good proven PL forwards in Son and Richarlison, not to mention a manageable wage bill.
Artetea inherited a mess in 2019 that finished 8th, his forward line was Pepe, Lacazette and Aubameyang, who's ineffectiveness was only eclipsed by their unprofessionalism, in a squad of players where all of them were paid 250k a week because of their crazy holocratic system.
I don't particularly rate Arteta, and us and Chelsea repeatedly shooting ourselves in the foot has helped, but he got them back into the CL, from a position where they could easily have disappeared into mid table obscurity, again.