These are some of the biggest and most profitable. With plenty of demand.
I thought it was a good list of specific areas to focus a business or YouTube Channel.
Niches of people where you can buy traffic rather affordably.
niches for digital ads
affluent home hunters
affluent investors
affluent real estate investors
art & culture lovers
art & theater aficionados
beauty mavens
busy professionals
car shoppers
cooking enthusiasts
dedicated diners
education seekers
engaged couples
engaged women
fashion-forward shoppers
fashionistas
fine diners
fitness enthusiasts
frequent travelers
golfers
high-end jet-setters
home decor enthusiasts
home hunters
luxury shoppers
men's fashion enthusiasts
news junkies
parents of school-aged kids
pet lovers
pet owners
savvy parents
sports fans
technophiles
travel buffs