Let me explain further. HTML is for saying what things ARE, semantically, grammatically, structurally. It is not for saying what things look like, and if not for the pissing contest between Microsoft and Netscape, it never would have been abused such in the train wreck that was HTML 3.2
Part of the fixes 4 strict and CSS brought to us is the ability to target different media targets for different appearances / behaviors. Print doesn't need the same layout or behaviors as screen. Aural, braille, and search engines could give a flying purple fish about what you want things to look like.
To that end <link> and <style> have a "media" attribute.
<link rel="stylesheet" href="test.screen.css" media="screen">
<link rel="stylesheet" href="test.print.css" media="print">
User agents should only load that first external stylesheet for screen media devices, and the second one for print. In theory. FF and IE love to load screen media on print even though that's NOT how it's supposed to work.
If you see a LINK or STYLE tag lacking the media attribute or setting it to "all", in all likelihood you're looking at those pesky 3i of web development. Ignorance, incompetence, and ineptitude.
Another of the advantages is improved caching. External CSS can be cached across pages that use the same style, or to pre-cache the appearance of pages the user hasn't visited yet. It is to this end that 100% of the time you see <style> and 95% of the time you see style="", that pesky 3i is rearing its ugly head again.
Same as how "presentational classes" piss on the separation of concerns and caching, since you're placing "what things look like" in the markup. Idiotic classes like class="text-400-grey bgColor-000-black box-shadow text-center col-4-s col-6-m" are a monument to 3i. A laundry list of how NOT to use HTML or CSS and proof that the majority of people who CREATE HTML/CSS frameworks like Bootcrap and Failwind aren't qualified to write a single damned line of HTML, much less have the unmitigated gall to tell others how to do so.
But the sad part is most people making websites learn from broken, incomplete, and misleading sources (see W3Schools or Udemy), which is why they get suckered into THINKING they have a "good handle on things" when they clearly do not.