The "C" (Cascade) in CSS doesn't suck, the education about it sucks.
People don't know how it works, then things go wrong so they learn to work around it.
That's what led to things like div + class soup that you get with the BEM naming convention or Tailwind.
The cascade is actually awesome, super powerful and if you know how to use it, it can greatly simplify your code.
Education is the problem and the solution.
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To anyone outside the CSS space, this is the closest analogy I can find:
In the American education system, there was a recent-ish change where children are "taught" to read using a method of just learning the shape of every word (e.g. "thermally" has a th at the start and ly at the end, so it must be the word "thermally", despite other similar looking words like thematically).
The method was disproven but the American education system still uses it.
Now illiteracy rates are climbing where almost 1/4 Americans (USA) can't read.
It's basically the same thing with CSS, where developers don't know what the code they're reading/writing is actually going to do.
I call it cargo cult developing. People develop bags of spells and tricks that they attempt to apply to a situation to solve a problem. Usually they can arrive at a solution by trying a number of these incantations, but not always. And never actually ask them what the incantation does
It's not just css either. At a job I've worked, we had a VPN client that would get into a weird state, where it needed to be killed to restart. An incantation that made use of ps, grep, awk, and xargs was provided, instead of just using pkill