"Also, the lack of address of real problems of tailwindcss of OPs comment in terms of mantainability is something you consider."

Not sure what you mean by that. I've been doing this since we did layouts with tables and shims in the 90s. I've found TW pretty nice to maintain myself.

"It's not that much harder", but a) it's a simple example and b) now you're going to litter your code with a load of hard coded media widths?

Let's talk about something concrete. Let's take a really simple layout that changes border and margin responsively (this, for me, is seamless).

    <div className="m-8 lg:m-0">
      <div className="border-2 md:border-4">
        Content
      </div>
    </div>

How would you do that?