You see it in the education system too. The left winger will want to design an inclusive education system where everyone gets the same treatment, to give everyone a chance to blossom. The right winger might see this as oppressive, because it doesn't give the best performers a chance to excel, as every kid is dragged down to the lowest common denominator. He never saw the children as having equal potential to begin with, so why have the naturally smart kids waste time together with the rest?
See, what I'm describing is a purified logically consistent version of the two wings. Hardly any real person is this logically consistent, and will draw a line somewhere, instead of pursuing their ideology to its logical conclusion. The logical end point of each wing is crazy, which is why most people never go that far. But why favor any particular side? There's no reason to. I can't be a right winger without taking it to the extreme, because my logic will take me there, not can I be a left winger without taking it to the extreme, so I stay in the middle.
I grew up in a Scandinavian social democracy, with Labor Party parents, so I know the left wing point of view very well: We're all the same on the inside. It's merely circumstances that make us different, so we all deserve to have the same things, and (if you extend that line of thinking a bit) we thus all have the ability to do anything, given the right nurturing. That, and nothing else, is what the cloned lab mice are meant to symbolize.
Perhaps there are cultural differences that are causing some friction here, then. Here in the US, the problem with the education system is that the funding mechanism for schools relies on property taxes. Affluent areas have well funded schools and schools in impoverished areas languish. The issue with education isn't whether or not students who have shown aptitude are allowed to flourish, it's whether children are able to achieve their potential to the extent of their abilities. There is a hard limit to what can be achieved by children from poor communities, while the children of the wealthy are nearly guaranteed success regardless of their individual talents. Add to the mix the racism that plagues our society...
So left wing approaches to education here attempt to mitigate the problems that come from inequality that actually prevent intelligent and talented individuals from achieving excellence. The same social factors allow mediocrity to achieve stellar results, due to inherited advantages.