its MUCH harder to feel bad that your missing something (i.e. the bais Hamikdosh or neviyim or even just what life was before the spanish expulsion with the rambam) when you have never experienced it. you need to be on a very high spiritual level to really mourn the bais hamikdosh on tisha b’av while the words of aicha are being said. even though the trup is a trup of mourning (just like yomim noraim chazanus is a more serious tune to wake us up to a feeling of teshuva)
may we all work on ourselves to start feeling our real losses that have still not been returned to us yet thousands of years later