Yes they are relevant. From the article, skills like "accessibility, progressive enhancement, network performance, interface design and user testing" are relevant to the ultimate goal of producing a web page. Front-end development is not merely implementing a design specification. The skills listed are relevant to transformkng the design specification into a web site/app that runs on the many devices and platforms and is used by a variety of users.
The design specification can include everything you mentioned. The article argues that "JavaScript frameworks have deskilled frontend development in the last decade." That's what I can't agree with. We need the simplest way to achieve the desired outcome. Using higher-level means to do that doesn't mean deskilling.
