Hm, somehow hoped for more details on the changes to the cores. Unified L3$ we knew for ages, and "Zero Bubble Branch Prediction" is the only new token brand we got to hear. What exactly are the improvements for Load/Store, and the changes to the issue width of int and float engines? I guess the event was squarely targeted at gamers, and have to hope wikichip or some other specialized site will get the info I'd like to hear about Zen 3.
The $50 rise for MSRP is unfortunate. But looking at other forums this was not an areas where AMD could have won over anybody skeptical anyway, most people were comparing street prices of Ryzen 3000 with these new MSRPs, of course the former are vastly lower with or without that imo rather small rise.
In AMD's case the MSRP always has been an early adopter premium. Honestly I consider the $50 rise rather low for what it is (and will wait for lower street prices as always

).
I highly doubt they used the top card. Even in this video they first presented the 5900X to then top it with the 5950X later on. Giving away the best possible numbers as the tease for the next event would be out of character there.