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Reasoning looks good,

I'm curious if it impacts performance in any way on Visual x64.

There's a slight perf gain when building with MSVC and targeting AVX2. (Using current VS 2022 preview)
I should double check the SSE behavior

When targeting AVX2, MSVC will use bzhi (bmi2 instruction). This only happens when targeting AVX2.

Reasoning looks good,
I'm curious if it impacts performance in any way on Visual x64.

There's a slight perf gain when building with MSVC and targeting AVX2. (Using current VS 2022 preview) I should double check the SSE behavior

When targeting AVX2, MSVC will use bzhi (bmi2 instruction). This only happens when targeting AVX2.

SSE seems ok; but not really that different.

(before change; SSE)
3#Lorem ipsum : 10000000 -> 2983345 (x3.352), 337.1 MB/s 1181.9 MB/s
vs
(after change; SSE
3#Lorem ipsum : 10000000 -> 2983345 (x3.352), 339.4 MB/s 1192.0 MB/s

When targeting AVX2, MSVC will use bzhi (bmi2 instruction). This only happens when targeting AVX2.

I thinks that's the main goal.
We observed that bmi2 gives a small but solid performance gain.
Enabling that should be beneficial.