@slightlyoff

Those folks you want to ignore seem to be the people who are getting paid well, so people learning for vocational purposes are going to follow the practices of these "not serious thought leaders" because learning fundamentals of HTML and CSS won't be enough to get hired and spending time practicing these skills will delay new developers from getting hired.

Only the people who have made a living and established a reputation in the field who then put in the effort on their own to practice the skill of reducing JS computational costs on user devices can try to sell the value of those skills. That value might not be as high as initially intuited, since saving well off users with the newest hardware computational cycles can be effectively zero and many businesses' revenues are disproportionately dependent on those well off users.

This is an externalities problem much the way pollution is an externalities problem. In the same way, shaming and finger wagging isn't going to have an effective influence on those whose livelihoods are tied to taking advantage of the externalities. Solutions for externalities problems require collective action, which almost always means regulations and taxes (but not always!).

I don't think people are anywhere close to organizing action on this particular externalities problem. But what could help to that end is good descriptions of the problem and good examples of the alternative methods. Please continue providing more of both.