I've noticed the same pattern, and I think it's down to 3 main trends. 1) smaller families compared with GPs' generation (when there were more kids, there was usually a good chance that several would stay in hometown or at least the state/region. 2) more divorces starting in the 80s, leading to more split spouses moving for a fresh start. 3) college degrees (particularly more specialized or advanced degrees) becoming more common, leading to 'following the job offer'.
As long as any of the GPs were still living, then it was natural for them to exert some 'gravity' and draw at least some of the kids and grandkids back for visits and holidays, but that dissolved once the last GP died, and that's when their homes were sold (neither home was inherited by the kids, in one case due to Medicaid clawback, but all the kids had their own places, even the local ones, and wouldn't have wanted it anyway).
In terms of my parents' generation/my generation, parents divorced and we moved away from my home town/property, but stayed in the same state. One of my two siblings remained in the state, the other two of us left and moved to opposite ends of the country. So my childhood property is still occupied by one parent (and we might or might not inherit, depending on how long he lives), but was never thereafter a particular 'draw'...in fact, once I started college I've only visited my father or any members of the paternal side of the family maybe a dozen or so times (I'm in my 50s now). Once he dies, it's very possible I'll never lay eyes on any of them again.
My mother never owned a property after the divorce, but her rentals still served as a bit of 'hub' of activity on occasional visits home (once every year or two, usually), until eventually we had to start supporting her and moved her to our town. That basically broke the link of the 'hub' effect, and my sister and I almost never go back to our home state now (despite a third sister and our maternal aunts and a bunch of cousins still living there). ETA: My husband and I do sometimes build travel around going to see/do things with friends that are scattered around the country. But what the OP said, about visiting family several times per year, has never even been our radar since we were in college. My husband has seen family of his maybe a dozen total times in 4 decades since he turned 18 and joined the military. He simply has no common ground with them and no real emotional bond. No hostility, just :shrug: I feel the same about most members of my family. I wish them well, but I'm not close to many and don't miss the absence.
It is a bit sad in the sense that I miss especially the 80s and 90s, when the maternal side of my family was still close and all enjoyed each others' company. But time, aging, life circs, etc. has really frayed those bonds. It is what it is. I have very limited opportunity to travel, and rarely use it to go back to my home state (which I love, don't get me wrong). I generally haven't been integrated into a 'social scene' or 'community' since college, though. My husband and I have lived here 20+ years, and neighbors have come and gone. I've known a few to nod to, but rarely remember their names. We have a couple friends locally, and a large casual network of business acquaintances. But there's nothing tying us to this neighborhood or this city at all, other than my husband's career. We've never had any love for the place we live, nor a desire to 'build a community here'. I mean, we actively dislike the place in a lot of ways and wouldn't have chosen to live here if it weren't for work.
My two sisters also live fairly loner lives (apart from their significant others), despite them both liking where they live much more than we do. The one still in our home state rarely sees our aunts or cousins, and has only some casual local friends that she hardly ever sees. The middle sister has a couple of good friends local to her, and fairly large work related casual network. But we are all kind of loners; plus, none of us wanted kids, so there's no 'grandkid' issue that drove us back to see family, nor is there the automatic 'parents' network that some people utilize to form midlife friendships. ETA: We three siblings are SUPER close, though, so we make an effort to see each other every year or two.
My impression is that social isolation and loss of community is on the increase in the U.S., so we are likely atypical, but not as much as we would have been several decades ago.
