If you are looking at Bitcoin from the angle of equality, you should look at it from the angle of equity, fairness and accessibility. Once you have your Bitcoin, you can use it as you like, like any other people (Rich or poor, Yankee or European etc) without any discrimination or rejection.
What you referred to is the reward for those who trusted Bitcoin when it was still doubtful, and if Bitcoin has enriched them, it doesn't matter (no partiality here). They are one of those who believed in it and made it have an early rise. This is a huge effort, trust and commitment that needs to be rewarded.
That is the way I see it. Has Bitcoin made them rich? Oh, Yes. Is the richness unjust? Heck No!
I definitely think OP is actually wrong in his assessment of bitcoin solving inequality. Bitcoin solving inequality doesn’t mean that everyone will be assigned same number of tokens or there will be limitations of what everyone can hold so some people do not hold more that’s clear centralization. It is an issue of money you can have all the money and decide to buy large bitcoin today and no one would be able to stop you because the network is decentralized. What Whales have is more money and Satoshi can not actually stop that. What early investors have is reward for believing in something had this gone south wouldn’t we have all called them fools. Calling for equality here is like saying Legendary accounts on this forum should be dethroned to same level as someone joining today what’s the reward for been supportive since day one.
Bitcoin gives equality in such a way that both the big investors or elites can buy and sell bitcoin just like a normal person. Both people can move their funds without actually having it censored in network, there is no distinction in the UTXO. Traditional monetary institutions didn’t give this equal opportunity and it only bitcoin giving everyone its own equal freedom