They have basically the same features. OGL might be a bit faster currently, but that's going to be contingent on how much time a developer puts into optimizing for a given API, and if there are any current driver issues.
The big difference is that OGL is a relative pain in the ass to code compared to D3D, which of course means there are fewer developers out there who have bothered learning OpenGL and transitioning over would be a pain when Direct3D is working just fine and there aren't many compelling reasons to pursue cross-platform PC support.
So, OGL is more than technically sufficient, it just has a barrier to adoption.
If you're a US citizen, please speak up for the unarmed black American men being murdered every week by the police. It's not about "social justice". It's about human rights.