That is inaccurate.
Molotovs do around half HP damage to bunkers. Two of them should leave a bunker with little health, 3 should destroy it.
You do now that "don't really scratch the german light bunkers" was an exaggeration to show that it usually not worth it to throw a molotov at a german bunker? So, maybe that wasn't clear to anybody so I clarify it now.
So my clarified statement is:
"UKF emplacements are pretty prone to fire. Even the simple OKW flame nades do high damage. On the other side german bunkers seem to be not prone in the same way to molotovs for example."
Simple comparison:
German bunker with 480HP dies to 3 molotovs
UKF mortar emplacement with 780 HP dies to 2 OKW flame nades
UKF Bofors emplacement with 1000 HP dies to 3 OKW flame nades
Something seems to be odd. Flame nades were meant to be a garrison/cover counter as they got introduced. For countering early mortar emplacements and Bofors later on OKW has a very early ATG, an AT handheld upgrade on starting squad (only partly usable vs Bofors) and ISG if going for Battlegroup HQ.