How can we be zocheh to Binyan Beth HaMikdash when you can’t be bothered to be Dan LeKaf Zechus?
“… if a Kohen who ate bread is sitting among them” What happens when the person who leads the zimun isn’t sure or isn’t paying attention? Perhaps to insist on this Kavod, a Cohen needs to have his Yichus certified by a Bais Din?
Besides that, look at Sha’ar Hatziune 65 where he says that there are situations where the person who leads the zimun does not need to ask permission from the Cohen. The point of this halacha is to be careful to avoid hurting anyone’s feelings when you take Kavod. Insisting on Kavod for the Cohen is exactly the opposite of what is intended.
Sinas Chinam is what destroyed it. Ahavas Chinam is what will rebuild it. The cohanim have their job, but the Levi’im have their job and the Yisroelim have their job. We would all need to work together to make it happen.