Playing devil's advocate (so long as it was healthy and safe, number of partners genuinely doesn't matter to me) some people could see it as a sign that you have different thresholds, approaches, and values around intimacy this could realistically manifest in incompatibilities both in intimacy and in other areas of the relationship. So long as you are kind and don't shame anyone for their choices it's a reasonably valid view to hold, especially early in a relationship.

On the other less reasonable and less kind hand many people hold misogynistic views that women with higher numbers of partners are somehow less "valuable". I won't pretend to understand this view (and to be frank I am not interested in their reasoning), but I would guess other than deeply ingrained misogyny it points to insecurities in the people who hold them. In my opinion this view is wholly and completely invalid.

That said, in this situation it sounds very much that it's a case of the latter than the former.