I lost a bird about 5 years ago now and I still get calls from people asking me if they found my bird
She wouldn't have to be loose for 5 years... Maybe she was found by someone and then escaped another home. So many things are possible. I would give ANYTHING to just know she was alive and happy and well. Knowing that people still contact me even when the chances are so slim that it's her rekindles my faith in humanity.
If there is a 0.01% chance this is someone's bird, at least give them closure. That does not mean blindly hand a bird over to someone, of course! Most people don't want "a bird that looks like their bird they lost". They only want THEIR bird or the knowledge that they didn't die outside.
It's the not knowing that eats me alive.