There's no distinction in class or group here. You're playing cute with the "equality and discrimination" bit which is clearly a red herring. Otherwise you need to learn what discrimination is.
Progress in society are made at points in time and it's not always feasable or possible to make them retroactively. Apply your logic to progress over time in laws, civil rights, ending of slavery, healthcare coverage, advances in medicine and treatments, transportation, wages, anything really and you'll see where your logic faulters. You have to make a better argument, starting with considering the contextual factors of the specifics of what your talking about, and then go from there. Does society benefit from this change would be an important question to ask.