MinnMan

I'm not sure if this is a sincere question or a troll, but the OP's comparison between marathons and bike road races is misplaced. There's no rational objection to women participating in marathons alongside men - it's an individual sport and it's possible to reward both the fastest men and women in the same event. Road cycling is a team sport. As previously noted, a woman could ride with the men if she had competitive strength and power, but otherwise, it wouldn't make any sense.

It is better to boost individual womens' events. The womens' tour doesn't get as much attention, and there are a number of reasons for this. But plenty of amateur women buy expensive bikes and gear - I think that there are some missed marketing opportunities that could be helped by greater visibility of women's racing.