Because these are normal instructions.

If you do multiplication using mul instead of loop and add, is it acceleration too?

Yes.

The article would then be "MUL-accelerated multiplication". Obviously any modern compiler should not require a developer to make that optimization.

What does "normal instructions" mean? I don't see (or missed) a heading with "Normal" in the ESP32 docs.

Edit: Or are you saying the instruction called out by the author is not SIMD?

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