Baseboard management controllers (BMC) vendors?

Does anyone have any opinions about BMC vendors? I noticed a Taiwanese vendor called Aspeed seems to be quite dominant, but are BMC vendors differentiated in any way, or is it primarily inertia because Aspeed is designed in & too much trouble to switch out, or do they actually do a good job of what they’re supposed to do? Seems like a small & cheap yet critical component of cloud servers.

And one more: will OpenBMC basically mean even less differentiation between BMC vendors, since the software offered by vendors like Aspeed will matter even less?

Thanks in advance for any opinions / insights here