As I understand it, the shaped charge, chemical energy penetrators for the RPGs are a relatively recent development. Since they are essentially a "point and shoot" weapon used at much more limited ranges than a TOW or other ATGM, the traditional countermeasures are generally ineffective.
In heavily urbanized areas, tanks are also highly vulnerable to attacks on the top armor, which is generally a lot thinner than front slope or flank armor...
Somewhere I hear the saying, “the only more dangerous place to be than inside a tank, is outside the tank”.
No. RPGs have been using shaped charges since the Panzershrek/Panzerfaust and Bazookas of WW2. The Soviet RPG has a number of warheads, the most common is a shaped charge in the RPG-7.