Doesn’t the girl in question have a job? How can she be home for lunch every day?
I definitely think supper should be eaten together. But that can happen away from kollel as well.
It’s a way of knowing that your husband really loves Torah. I don’t see why Torah can’t be part of a boy’s life if they are working as well, but the truth is that from my experiences in shidduchim, finding boys who are serious about Torah as well as supporting a family is like finding a black grain of sand. They’re definitely out there, but if you decide to marry a kollel boy, it’s a lot easier to find someone who loves Torah.