It makes intuitive sense that going wide in SIMD uses less power than going wide over cores, because extra SIMD lanes take up much less silicon area than adding another whole core. If they didn't then we wouldn't bother with SIMD, we'd just make more cores and save ourselves the hassle of juggling two different types of parallelism.
GPUs take this even further by going even wider, with each "core" typically executing 1024-bit SIMD operations (i.e. 32x FP32, 64x FP16, etc). CPUs have roughly settled at 128-bit (most ARM) or 256-bit (most x86) with a little bit of 512-bit (x86 with AVX512) which grew out of Intels earlier aborted attempt at making a dedicated GPU.
GPUs take this even further by going even wider, with each "core" typically executing 1024-bit SIMD operations (i.e. 32x FP32, 64x FP16, etc). CPUs have roughly settled at 128-bit (most ARM) or 256-bit (most x86) with a little bit of 512-bit (x86 with AVX512) which grew out of Intels earlier aborted attempt at making a dedicated GPU.