I think most Arsenal supporters definitely expect much more robust cup challenges going forward. A big part of the issue in the FA Cup the last couple years was just tough draws - playing City and Liverpool in the first or second game and losing narrow matches against them. Shit happens in cup football. But we should try harder in the League Cup, which Arsenal as a club has never really taken too seriously. To win that competition you generally need a very deep squad (like City and Liverpool have had recently), a manager who really prioritizes the competition and doesn't rotate, or a ridiculously easy run of ties. I think we now have the squad to put out a relatively strong side even when rotating significantly and I hope we take that competition more seriously. The new European format will make it difficult, however, as the last two CL matchdays are basically right around the same time as the two legged League Cup final so if you're juggling both you'll end up with an insanely busy January instead of using that time as a mini-break or reset period. So we'll what happens.
We could take a step backwards but the squad also has room to improve. No doubt some more challengers will emerge, but I think City will take a big hit as I expect Guardiola to leave after this year almost regardless of the outcome of the case. And for a lot of important players like KDB, Bernardo, Stones, etc to see that as the time to move on too.
IMO, the future is bright and I would certainly bet on us winning at least one PL title under Arteta.