Studies on gender disparity in academia generate constructive discussions to promote equality. In a recently published study, AlShebli et al. 2020 analyzed the role of informal mentorship in supporting early-career scientists and how gender may shape scientific careers. Besides presenting methodological flaws, the study culminates in the authors' conclusion that mentoring quality is determined by the mentor's gender, suggesting that female protégés reap more benefits when mentored by males rather than equally-impactful females. Despite acknowledging that possible causal factors were not considered in their analyses, they attest that the success of female scientists' careers relies on opposite-gender mentorships in terms of publication and impact. Although the authors state that these findings add a new perspective to the policy debate on the best ways to elevate the women in science, their conclusions reinforce the traditional patriarchal, biased scientific structure that stimulates a poorly diversified hierarchical chain in STEM. Here we highlight the study's methodological weaknesses and major issues that must be addressed to avoid the perpetuation of gender disparity in science.