Planes, trains, automobiles.... people travel.
Some do, some don't. My mother and my MIL have only ever met once, at our wedding. It was certainly out of her comfort zone to travel, but she did for that occasion. My family never met my FIL because FIL would not travel. And it's not just one-sided. My mother doesn't like to travel either, but she had the advantage of the wedding being local for her. I don't exclude myself from this trend, buy my reasons are different. While I agree with your list in theory, I just can't picture it playing out on a practical level for a long-distance relationship, especially if the families are not both Traditional Catholic.