I dislike tailwind too. Maybe I just use it wrong. But if I say have a number of similar-ish elements with many overlapping classes, when I need to make a change it affects numerous lines of code.
Traditional CSS? I’d update a style in a few specific spots and everything benefits.
You can still use normal css if you're styling multiple things. I think tailwind shines mostly when the css does not need to be reusable or is encapsulated in a component which is how it works in some modern web frameworks.
The reason why it is big is efficiency. Once people know those class names by heart, they get a "nice" (arguably) default style very quickly without jumping between multiple files. This matters more than one might think..
Traditional CSS? I’d update a style in a few specific spots and everything benefits.