Itanium, XScale (ARM), Altera FPGAs, Intel Arc GPUs, Intel 8051, Larabee.
Intel has repeatedly tried (and with $Billions invested in Itanium particularly) to build a new architecture. It just turns out that x86 is way better than anyone ever expected in practice.
AVX512 is very well designed in any case. Intel knows what they're doing. If you want cool assembly instructions, I suggest learning AVX512 as well as the PEXT and PDEP instructions. I'll pointout the AVX512 compression and expansion instructions in particular, as proof that Intel's engineers really know what SIMD-compute and how its useful.
Intel Arc GPUs are also interesting, though not as commercially successful as AMD or NVidia, it shows that Intel has substantial investments into SIMD compute patterns as well.