I never said people SHOULD observe Yom Hashoah, just explaining a bit why it was pulled out.
No one thinks Yom Hashoah has a specific religious significance. Its a day of commemoration. It doesn’t take anything away from Tisha B’Av and no one I know who observes Yom Hashoah observes Tisha B’Av differently because of it.
DY, perhaps things have changed, but my RW school didn’t discuss the Holocaust very often and certainly less than once a year. I was exposed to it greatly from my grandparents, relatives, books, trips to Yad Vashem etc. My camp didn’t really do much either.
I do wonder if the reluctance of the RW/Charedi camp has more to do with politics than hashkafa. (Although, we could debate on how different they are, but different tangent really)