The tooling around CSS has evolved quite a bit since we started the "one-rule-one-class" approach to styling (Bootstrap released in 2011.) When the best web fra

The tooling around CSS has evolved quite a bit since we started the "one-rule-one-class" approach to styling (Bootstrap released in 2011.) When the best web frameworks can deal with attributes, but not with CSS rules, it makes sense that's where we go. But then you see a fork in the ecosystem, where some continue working on the semantical side, and some just want "Bootstrap, but with X and Y, so I can finish my project". I think the article argues against continuing down this latter branch. With CSS preprocessors, variables, media queries, calc(), transitions, animations, layers, no IE, etc. we're in a very different position today. Everyone's now used to using JS bundlers, i.e. a build step. Webpack was released in 2014. Accepting that source and distribution are separate makes it much easier to motivate going for a preprocessor and being able to write nice CSS.