The right might not realise why they are disliked

We cannot expect the right to realise that fptp is a problem. The left enjoy first past the post because they collect extra votes from people who are dissatisfied with the right for reasons other than economics. If we can characterise the right as a combination of economic liberalism and social prejudice then the right will lose economically liberal votes because of their social policies. This will be advantageous to the left and we can understand why the left would support (or not seek to replace) first past the post. Even though the left support fptp the right do not oppose it because they cannot see a problem and deduce that the population are more to the left (economically) than in reality. They ascribe all votes for the left to economic collectivism and none to being appalled at the social prejudices of the right. The right assume (wrongly) that all votes for the left are to do with economics but in reality the right lose many votes for their social policies. Because the right do not realise why they are unpopular... assuming others share their prejudices... they see no reason to be against fptp. The right are fine with fptp because they are unaware of their prejudices and so do not realise it is for these reasons that they are losing votes to the left. Or if they are aware of this dynamic we could say that the right prefer to keep their socially oppressive policies than oppose economic collectivism. Either they are unaware of their prejudices or would prefer to keep their prejudices even if losing them could achieve economic liberalism. They care more about oppressing innocent people than liberating themselves (assuming they are aware of their prejudices).

The right might not realise why they are disliked but if they do they are hurting themselves merely (because they want) to hurt others.