I agree with BikeRider. Old can be really bad. As much as I’d like to live a Central San Diego, the houses that I’ve seen really need some major updating. I don’t mind buying an old house if it’s discounted enough for me to afford to do a major remodel. No HOA or Mello Roos help finance the remodel.
New houses generally use better technology. I can tell the difference between a house built in the 1980s and one built in the 1990s. The joists are better in the 1990s house and you don’t hear the floor creaking. New houses are also better insulated, have better windows and require less heating and cooling.
Old houses are well-build only if they were large houses built for the well-to-do. Old tract houses from the 1950s-1980s are bad. 1990s onwards is better.