You can't lose many sales to something that isn't there. Outside of review sites and forums, scalpers and bot watchers, there's no Zen 3 to speak of. And to that point, 80% of AMDs 7nm production was slated for XBox X/S and PS5. 85% of the market in client is via 7 OEMs and not one of them has a Zen 3 based system. Zen 3 will probably become a real threat Q2 2021, right now it's a marketing move.
When you see one of the major OEMs like Dell, Acer, Lenovo, Asus, HP selling Zen 3 boxes you'll know it's arrived. It is important for mind share, but I think Intel knows that, and have things timed accordingly. That's why RKL will be there when Zen 3 isn't paper anymore.
So the big question will be, how will RKL perform, and how far up and down their product stack will it penetrate. That mindshare thing is actually pretty important too.