People often tout "separation of concerns" but it really doesn't apply here.
The important concerns to separate are business/application concerns. Putting your JS in .js files, your CSS in .css files, and HTML in .html, it's separation of languages. You could argue that the three languages solve different problems but this isn't true. We have JS writing DOM nodes which HTML does intrinsically, we have CSS and JS doing animations, we have CSS that does styling but also CSS that does layout, HTML nodes that are sometimes there specifically for design or layout concerns. We should be focused on components here, which use the three technologies to solve one business/application problem.
Tailwind can get a little ugly, but you are supposed to use it in conjunction with components. Personally, I don't find 10 inline classes that much harder to read than 10 style rules on 10 lines.
The important concerns to separate are business/application concerns. Putting your JS in .js files, your CSS in .css files, and HTML in .html, it's separation of languages. You could argue that the three languages solve different problems but this isn't true. We have JS writing DOM nodes which HTML does intrinsically, we have CSS and JS doing animations, we have CSS that does styling but also CSS that does layout, HTML nodes that are sometimes there specifically for design or layout concerns. We should be focused on components here, which use the three technologies to solve one business/application problem.
Tailwind can get a little ugly, but you are supposed to use it in conjunction with components. Personally, I don't find 10 inline classes that much harder to read than 10 style rules on 10 lines.
To each their own, of course!