Studies do indicate a statistically significant difference in response rates from VCs in favor of women. But only ~10% difference, not something decisive: https://www.economist.com/graphic-detail/2020/01/10/do-ventu.... But claiming that just because there are more male founders than female founders there's bias against women is a very simplistic approach. As other commenters point out, there's already a disparity in representation among the applicants.

And you go too far in your last sentence. Saying that there is an existence of bias is not saying that people's achievements are the product of their identity rather than their ability. Just that their identity played a factor in having that opportunity. E.g. one of my past employers gave women and URM 2 chances to pass the phone screen and move to the onsite instead of one. This is definitely a bias. But the people that got hired still had to demonstrate the same level of ability in the onsite interviews. Bias just let more of them have that chance. It didn't result in unqualified candidates getting hired, it reduced the false negative rate for a certain segment of candidates.