The example though uses a three dimensional vector and suggests turning that into an SoA form.

My question is: In the case of component vectors like that, given that many operations wind up in operations like dot products, do the advantages still apply?

I don't have any experience programming with simd instructions specifically, so the memory access patterns get a bit murky to me.

The same goes for cuda, for example, which has a native float4 type. It's making row ordering so convenient, and going for SoA seems like you need to walk away from that.