If they are practicing incorrectly then yes, the ideal of equanimity can lead to some people repressing their feelings. However the ideal of equanimity may not lead to some people repressing their feelings if they are practicing correctly, because it is more the process, not the ideal, that is preventing them from understanding. The process that enables them to realize the ideal. The ideal of enlightenment, the ideal of equanimity, the ideal of purity of the mind is not something that causes us to practice incorrectly. It is ignorance of the process to get to that ideal that prevents us from practicing correctly. So if we have ignorance of the causes that lead us to reaching the ideal of equanimity, then it could lead to some people repressing their feelings.
So it really depends on whether we are trying to open with objective awareness to what is arising in the present moment and allowing ourselves to investigate with equanimity into that with neither liking or disliking so that we can understand the results of that and bring about compassionate understanding. Understanding that the feelings arising in the present are the means by which, having awareness of them, investigating into them, having compassionate understanding of them, are the means by which we will reach the ideal of equanimity.