GoKawiilIn my own case - as I believe is normal for HDMI spec - displayport does allow better/higher refresh rates. But its also the case that multibooting with something like rEFInd you would be starting up your system on displayport, and then having to switch over the output to HDMI manually (eg using monitor controls), and then back over again manually later. It’s also the case that on systems with graphics cards like these, the user might also use multiple extra displays or (again, in my own case and I know for others) particularly for VR headsets which require HDMI and don’t respond well to adapters. Constantly swapping HDMI cables in to the output on a graphics card is… not great, even in the short term.
And it does make a difference to how much some people are willing to use Haiku if they can just have it there ready to boot up every day without having to mess around with monitor input controls, or (fragile/in use) graphics card outputs.
Hope that makes sense!