I don't think he is. I don't think he's better than Martial, Rashford or Iheanacho
I don't think that's the reason we haven't got a better striker either. Wenger has tried to land Suarez, Higuain, Vardy, Lacazette, Aubameyang, David Villa that we know of. We've just been incapable of pulling any of those moves off.
If he doesn't want to ride the bench who in their right mind will pay his 100k a week wages?
You don't rate him, that's fine. I do.
I think he is good enough if he shares the responsibility for scoring goals through a season.
Trying to buy Suarez was more of a RvP moment, Arsenal thought he had a release clause, not trying to get him when he was in that form would've been stupid.
Vardy and Lacazette would've been players to share the responsibility with Giroud, while I'm unsure if I've ever seen any substantial rumors about Auba to Arsenal, and David Villa is a blast from the past... I'm talking now though.
I can accept that you and a lot of others don't rate him as good enough for your club. And you guys obviously watch him more than I do. But since he came to England, based on what I've seen, I've seen a 20-goals a season striker that struggles when he is off-form or jaded (which keeps him from reaching those numbers), and a proper partner to share the responsibility and lowering the gametime he had would help him I think.
Btw, with squad-role i mean more or less what we United fans think Schneiderlin/Fellaini/Lingard could or should be, players we can have in the squad but don't want to use in a first XI. Giroud is too good for such a role, and would be more in line with, say for example Juan Mata. Someone who absolutely can and should start every other game when he is in form, and come in when we need his kind of qualities. A bit more than just squad-filling.
I'm starting to go around in circles though, so i'll leave it there.