Do you? I'm sorry but Tailwind takes quite a lot out of the CSS equation. You only have to learn what each property is doing. Then for example C for cascading, being a great feature of CSS, which with Tailwind you don't even need to know it exists.
Yes, you absolutely still need to know how CSS works. You're still using the box model, you're still using floats and flexbox and negative margins to position things, and the most important aspects of cascading still work.
Tailwind is just shorthand for CSS prop/value keys that also gives you an easily customizable and maintainable design system, which an increasing number of developers understand. That means that you can be productive immediately on a new codebase instead of having to spend hours getting your head around the multitude of CSS files that may or may not have been organized in a way that makes sense to you.
> you're still using floats and flexbox and negative margins to position things
See - floats and negative margins are one of the code smells if are used to position things (yes, they have valid applications but in very limited use cases) that make me believe, that if you are still using them in 2021 then my worries about how Tailwind make dangerous shortcuts are valid.
You don't need to use them, but since they are valid ways of positioning things in CSS, Tailwind has utilities for them. They're as 'dangerous' as they are in handwritten CSS. You can get by with only using flexbox and absolute utilities and that's great.
Do you? I'm sorry but Tailwind takes quite a lot out of the CSS equation. You only have to learn what each property is doing. Then for example C for cascading, being a great feature of CSS, which with Tailwind you don't even need to know it exists.