anxious poop eating?

hi. i have a 10 yr old gsd who loves eating poop. the problem isn’t him eating his own poop anymore but instead other dogs poop. he doesn’t do it all the time, really just whenever at random. there can be other dog poop in the yard he goes to the bathroom in and he will completely ignore it. he’s had a poop eating problem ever since i got him in august and we’ve been able to get rid of the constant poop eating with toys, more enrichment and stuff like that.

but particularly it’s noticeable and able to be predicted after he sees another dog. a bit ago, i took him outside and usually when he goes to the bathroom we walk the whole block. he’s smelling around and there’s some other dog poop, which he ignores, completely, and is about to continue about walking. however he sees two golden retrievers across the street, perks up, and immediately dives to eat this random dogs poop he had just lost interest in. he continues walking but is obviously super excited by the golden retrievers who aren’t even in sight anymore, and he slowly begins to calm down.

this seems to be a reoccurring thing. he’s already reactive to dogs and gets super excited when he sees any type. sometimes he mistakes peoples bags for dogs and gets really excited before he realizes it’s just a bag and then moves on with his walk. the previous owners told me he was on anxiety medication a while ago when i inquired about him being super anxious with other dogs (not even meeting them but just seeing them drives him nuts) but for some reason they stopped it, not sure why. maybe he’d benefit from it?