The anti racism movement in America, finally bringing the ideals of inclusion, diversity, and equity to the forefront of the social consciousness and giving a voice to marginalized peoples in America and beyond.
Honestly? Given all the political upheaval and nations moving away from trade and looking inwards I’m surprised there’s not another world war. So I think the greatest accomplishment of the 21st century is that there’s still relative peace and we don’t live in the aftermath of a nuclear winter.
China's economic development comes to mind but curious of other contenders.
Solar power, commodity hardware, and of course distributed ledgers