People tend to have friends and family they want to visit regularly. So they try plan their life around not moving too far from where they grew up. That means people won't even look at a move of 125 miles away if there is not good transportation back. In turn if the high speed route between the two destinations they won't move there and in turn won't be making those trips.
Note that I said route above, not highways. Trains, boats, airplanes, cars, or anything else you can imagine works. The method of travel doesn't matter at all. What matters is how long it takes, and that you would use it for the trip.
Half an hour door to door (by whatever travel means) means you can have dinner after work with those friends once in a while. 1 hour means you can visit every weekend, but you lose those dinner mid week dinners. 2-3 hours means you visit for every minor holiday, but it isn't every weekend. At 4-6 hours every visit is an overnight. At 8+ hours this is a week long trip.
The above ranges are guidelines, not rules, they get fudged and overlapped all the time depending on various details. If the trip is 5 hours by train you might still do it as a day trip since you can plan to nap on the train. Even if you have to drive 6 hours each way: you might attend a funeral and return all in one day.