They may also support daisy chained display port or display port hubs.
I personally agree with you. They really should have had at least another display port.
Honestly another display port and one more HDMI would have been awesome.
Regardless they had plenty of space to put more in.
Talk to AMD support about what your choices are with their card. https://www.amd.com/en/support/contact-email-form
Or talk to the AIB partner support departments if you are going to get one of theirs.
I will mention @fsadough . He is on the pro side of the cards but he has been in the past the best expert on these connection questions, so maybe he can answer exactly what you would want to add to get a 4th display port connected to RDNA2.
I think 3 display ports, and a usb c plus an adapter for displayport to hdmi would have made the most sense. Displayport can do everythin hdmi can plus some, and usb c is nice for those of us that have vr headsets that support them. Also, eventually everything will likely be usb c cables.
He is talking about the new 6800 and XT that only have the one HDMI and 2 Display ports. What are the options for hooking up 4 monitors. And what additional hardware might be needed please. I assume he could use 4 display port connections and maybe a mix of 1 HDMI too if need be.
DisplayPort can daisy chain with the right monitors. So you could get 4 DP monitors (2 x 2 daisy chained), then 1 hdmi, and 1 usb c. That is a whole lot of monitors.
I personally just have a giant 4k and that is great for me, but to each their own. Hope you find a solution you are looking for. I also have not found a max total resolution, or max monitor listing, so it may not be released at this point. Would be nice to know.