I disagree completely. I've worn several hats at every job I've worked at, each one demonstrating a different skill set. I will reword, change the order of, or even completely delete or swap out bullet points under jobs to highlight the skills that a particular req is looking for.
If you're "just another developer" applying to a "just a developer" req, then yes there's probably no reason to tweak. For anything else, you should absolutely be reconfiguring your resume to highlight your relevant skills.
Cover letters are not really in style right now. But, even then, it still helps to align your resume to what you write in the cover letter. It wouldn't look good to talk about all this good stuff in the cover letter, and it has no visibility in your resume.
I disagree with that assertion. When looking for my current position, I had a much higher response rate when each resume was tailored to the position.
Tailoring, in this case, meant relatively minor tweaks - if it was a more engineering role I'd highlight those skills and contributions whereas with the more data science-y roles I'd highlight more relevant aspects. I think it's very arrogant to think that a single resume is appropriate for every job application.
If you're "just another developer" applying to a "just a developer" req, then yes there's probably no reason to tweak. For anything else, you should absolutely be reconfiguring your resume to highlight your relevant skills.