Regardless of who is buying homes, from my perspective, as a native San Diegan who owns a lot of real estate here (especially in CV), it’s been extremely interesting to watch the demand in this area grow over a period of 25+ years.
IMO, this area would not have developed to the frenetic degree it has, were it not for the evolution of companies such as Qualcomm, etc.
In fact, there was no Carmel Valley when I was growing up in La Jolla, and, eventually, when the development of the area was put to a vote, many voted against it.
San Diego has always been a great place to live, but it took jobs to bring the masses here who are in search of housing, and, currently, demand is greater than supply.
Fairly recently, perhaps, different dynamics have entered the picture with more investors, etc., but, IMO, the demand is primarily from families who want to live near their workplace.