Well, maybe you don't at you table... but that has never been a rule even close to being run at mine. I have no idea if that is actually in the rules (and couldn't care less if it is)... but the idea that there is no way to tell the difference between a Wizard casting Wish or casting Mage Hand is just silly in my opinion. At my table (and I'm pretty sure at many others), of course the counterspeller knows what spells they are attempting to counterspell because it's just stupid and pointless otherwise.You don't get to know what spell is being cast before you counterspell it. Smite is the same as fireball which is the same as wish as far as the counterspeller knowing what spell is being cast.
Seeing how your table runs counterspell, it makes it much more clear to me why you seem to be so against all of these proposed changes... because how you all are running the game seems to be in a very specific manner with a very particular way of reading and interpreting the rules that I tend to think is not how most of the rest of the playerbase does (and why WotC seems fine with the changes they are proposing for us that you are so against.)
Now there's nothing wrong whatsoever if your table runs Counterspell the way you do... your table, your rules. But at some point you might have to admit that your way is not considered the conventional way, and thus WotC's idea to make Divine Smite counterspellable is not the doom and gloom scenario for the rest of us that it might be for you, and thus trying to convince us that it is will just fall on deaf ears.