In what universe did Zen 1 fail? Zen 1 was one of the best-performing designs in the world and scaled very well to high core counts.
The fact that Zen 2 is better doesn't reduce the excellence of Zen 1.
The fact that Zen 2 is better doesn't reduce the excellence of Zen 1.
Failed in the context of NUMA, not the product or uArch. Which is still an issue with Zen 2. Only better managed.