With the money coming from where? Races I'm afraid are a capitalist venture and public interest generates sponsors which in turn generates bigger races and prize purses. If no one stands to make money from a race it won't be run and unfortunately that seems to be the case.
Fortunately in triathlon where no one cares about pros we can use all the age grouper entries to cross subsidize both mens and women's racing (there was a time when triathletes actually cared about pros). I would generally agree with you that there are more men than women following sport in general, so the advertising eyeballs generally come from men. I am watching Premier League Football right now and there is no women's soccer to watch on TV EVER aside from the Olympics. So cycling is not the only sport with this challenge.
But, why is it any more interesting watching a men's cycling race than a women's race. The reality is that none of us can visually tell how much faster the men are going. I can visually watch women's soccer and men's soccer and see a big gap in ability level. In cycling, I can't see anything. In XC skiing, I can't see any difference. In swimming I can't see any difference. So really the only diff between men's and women's cycling is just how the racing is presented to the audience. This requires some level of effort by the media and race organizers to actually present the sport. This is a chicken and egg argument. As I said earlier, the battles between Jeannie Longo and Maria Canins in the 80's in the women's tour and giro were pretty legendary if you got to watch, and read about it (I am a French speaker, so got to follow it all in the print publication L'Equipe).
There is "no interest" in women's cycling, because WE (I use that collectively as it is generally men in their 40's to 60's) controlling media and race organization don't have a will to present women's racing. There is no good reason why men cycling fans can't get equally excited by watching women's racing vs men's racing. The Rio Olympics road race on the women's side, was one of the most interesting bike races of 2016 and women's track is just as interesting as men's.
The no interest is due to lack of will by media and organizers, it has nothing to do with the actual sports competition. The only way to change this is media and organizations. Triathlon generally got it right out of the gate. In XC skiing, the women stars are the racing is generally well received by media and organizers have to have the women's races, so it's not even an option to cut their racing out of the loop.
Most of the sports where there is "no interest" in women's racing are older established pro sports where the media is locked into showing men's racing and competition only (think big 4 in North America, Soccer, Cycling)