According to :

It's easy to use a lot of wire in a new home, especially if you're
fond of home runs. I'm a fan of doing things that are useful and make
sense. Using #12 on low-power circuits isn't worth wasting money on,
particularly if it's borrowed money. It may seem like a small thing,
but by the time most people have paid off their home loan, they'll
have worked at least an extra week to pay for that wasted copper.

Ectually, I'd consider putting two dozen single low-moderate wattage
fixtures on individual dedicated/homerunned 15A circuits to be a vastly
greater waste of money than picking 12ga over 14ga, but perhaps that's
just me.

You probably could have put all of the fixtures on a handful
of daisy-chained 15A circuits or even 12ga/20A circuits and
saved a heck of a lot more than picking 14ga over 12ga.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.