Actually I would have predicted Zen. You're either really young or need to brush up on your AMD history. Historically, AMD had one-upped Intel at every corner and whooped their butt for years. They brought the 64bit extension to 32bit, and killed Intel's IA-64 goals dead in the water. At one point, AMD was in most datacenters. Intel's major save from the Pentium 4 era was their Core 2 Duo. I won't even go into the hot mess that Pentium D was, emphasis on HOT MESS. AMD has always been an innovater. That is a fact.
However, to expect a 50% increase in performance over RDNA... that's dreaming. I'm sure it'll be good, but the environment that NVidia have developed over time isn't there. This isn't really an AMD fault either. If you're old enough to have owned ATI cards, you'd know they were terrible in software, too.
I knew about Zen long before it came out. If you paid attention to the tech press, you would have, too. Maybe you did, I don't know. I was impressed with Zen. I was impressive with Zen+. I was and still am impressed by Zen2. I know Zen 3 is going to be very good. However, my big question is not whether TSMC can provide in the future. They have to or they lose their major customers. I'm wondering if AMD can continue delivering excellent performance gains per generation.
I don't have a lot of confidence in Intel's rumored 11th gen desktop, Rocket Lake. I have almost zero confidence in Alderlake. I'm sure they'll deliver it, eventually, but as for it being a beast? Heck no.