To achieve that tho you need a ton of superfluous non-semantic html wrapping everything in triple so that you have the flexibility to do what you need.
Also, just anecdotal: I am working on a Vue.js component which I want people to customize the styling however they want. This is forcing me to drop the CSS part of the components. I am not adding any cruft HTML and yet I did manage to get a "basic" theme and a good chunk of the "materialize" look already. Two themes, two separate SASS projects. It can be done.