E cores ruined P cores by forcing the removal of AVX-512 from consumer P cores
Which is why I used AMD in my last desktop computer build
That's finally set to be resolved with Nova Lake later this year, which will support AVX10 (the new iteration of AVX512) across both core types. Better very late than never.
I love the AVX512 support in Zen 5 but the lack of Valgrind support for many of the AVX512 instructions frustrates me almost daily. I have to maintain a separate environment for compiling and testing because of it.
E cores didn't just ruin P cores, it ruined AVX-512 altogether. We were getting so close to near-universal AVX-512 support; enough to bother actually writing AVX-512 versions of things. Then, Intel killed it.