The Article more-or-less speculates that: > Zen 4 is AMD's first attempt at putting a loop buffer into a high performance CPU. Validation is always difficult,

The Article more-or-less speculates that: > Zen 4 is AMD's first attempt at putting a loop buffer into a high performance CPU. Validation is always difficult, especially when implementing a feature for the first time. It's not crazy to imagine that AMD internally discovered a bug that no one else hit, and decided to turn off the loop buffer out of an abundance of caution. I can't think of any other reason AMD would mess with Zen 4's frontend this far into the core's lifecycle.