You still seem to be subcribing to an alternative definition of an overrepresentation. Whether or not factors influence the baseline population does not lessen the objectivity of measuring representation. You seem to be under the impression that the definition of an overrepresentation is, "having representatives in a proportion higher than some perceived ideal average." While under this alternative definition it may be fair to say whether not not a representation of women higher than the current average is a subjective statement, I am speaking in terms of the actual definition of the word which refers to representation with respect to the current average - not some perceived ideal average. When the proportion of women in tech is 20% and a company's proportion is greater than that, then an overrepresentation exists. The fact that you may think the proportion of women in tech may be greater absent certain factors does not affect the objectivity of that statement.