Indeed much of it is "functionally superfluous", but it does serve a purpose. For example Lowe's presents itself in a different way than Home Depot with friendlier colors, different typography, and messaging that on the surface may seem inconsequential. They sell the same things as Home Depot but it's those nuances that appeal more to women.
Simple and to the point designs often lack personality. And if you're trying to build a brand your site design needs to have a point of view.
Absolutely. But personality is an aggregate of style, design, functionality and so on. Style, design and functionality are additive to a great degree — you can add more functionality and splatter on as much stylistic flourishes as there is visual space available.
For example, the minimalistic Japanese "no-brand" (it's very much a brand) MUJI has very little actual style, but lots of design. It's simplistic and function-oriented. And yet the personality is often immediately recognizable. IKEA is often minimalistic, but has a significant brand presence without applying a whole of style.
Style is like makeup. You're not making a cake, so you have to be careful about how much you apply. Too much makeup and you come across as desperate or insincere. Too little and your wrinkles will be showing. I don't know how far one can stretch this metaphor -- you get the point. :-)
Simple and to the point designs often lack personality. And if you're trying to build a brand your site design needs to have a point of view.