Being Gen X there are a lot of us who are now grandparents, what is the joy? Is it the fact your kids having their own kids or it's because the family name continues?

Again, the higher the education, the higher the likelihood they will keep the name with which they were born. So, yes, fairly uncommon until you are in areas of society with higher achieving women. It often comes back to which doors young women see as open to them. My daughters are a dentist and a Ph.d research scientist / administrator at a major university. They both kept their names from birth, but they also knew we don’t care about “name continuation”. Look up the poem Ozymandias, written in 1818 by Shelley, to get an insight into why name continuation is really, rather pointless in the annals of history.