There is a SINGLE TANK IN WHOLE GAME which Tiger doesn't penetrate reliably.
You know, that is quite debatable. Because if we replace the term "TANK" with "CALL-IN" which will be more accurate, things change. Because currently you can dispose of a Tiger with your dual 85s call in. Further, assuming the difference in range betwen Tiger and a TD with turret (therefore behaving like a tank when fighting against tanks), I can theoretically assume that a Jackson can dispose of a Tiger as well due to the fact I can keep my jackson's range advantage by constantly reversing and shooting with my recently buffed AT gun.
If we are tot ake into account all the aspects on the field, and all factions, involving the fact that every conscript or rifleman will be eventually able to damage the Tiger's engine through AT grenades, it's easy to understand why Tiger is not in a good spot right now. And don't tell me that grenadiers have pzfaust too, because, you know, volks have nothing to damage an engine.
There is no comparison between the IS2 and Tiger armor, especially when we talk about frontal armor which is the most important.
And it's not about krupp steel love or other stupid things you want to imply, it's about the fact that Tiger has no defined role right now. To expensive to use it as an AI unit, to bad to use it as an AT one. It's good at everything and in the same time good at nothing really.