I've come to realize that some buyers in this area just want new and don't have much of an idea about anything outside of that general North Irvine new home bubble. Reason being, there are a lot of FCBs or international buyers. Also people moving from other areas who are unfamiliar. Your sentiment is my exact sentiment, but probably because we are familiar with the other options.
I know people who bought in those new areas that don't even know what south of the 5 or 405 even are because they simply don't go to those areas. I go all over town, but I've always frequented the southern side of town for things and I have a friend in Stonegate who goes to the Market Place, Northpark, Tustin, and even LF and literally never has a reason to go to Woodbridge, Oak Creek, Westpark, UCI area for dining and shopping.