as they say, “the well was never full until it is empty”- you don’t appreciate something until it’s gone, so too the other way, we can’t, or at least it’s hard to appreciate the fact that the beis hamikdash isn’t here until we know what we are lacking, so it’s hard but we gotta work on it and try
also, we can’t just expect to walk into davening and when we get up to es tzemach, feel sorry and start crying for the beis hamikdash/mashiach, we have to make it part of our lives