What a nice comment!! This has been a big failing of my mental model. I always believed if I was smart enough I should understand things without effort. Still trying to unlearn this....
Unfortunately you must look closely at the details to deeply understand how something works. Even when I already have a decent mental heuristic about how an algorithm works, I get a much richer understanding by calculating the output of an algorithm by hand.
At least for me, I don't really understand something until I can see all of the moving parts and figure out how they work together. Until then, I just see a black box that does surprising things when poked.
It's also important to learn how to "teach yourself".
Understanding transformers will be really hard if you don't understand basic fully connected feedforward networks (multilayer perceptrons). And learning those is a bit challenging if you don't understand a single unit perceptron.
Transformers have the additional challenge of having a bit weird terminology. Keys, queries and values kinda make sense from a traditional information retrieval literature but they're more a metaphor in the attention system. "Attention" and other mentalistic/antrophomorphic terminology can also easily mislead intuitions.
Getting a good "learning path" is usually a teacher's main task, but you can learn to figure those by yourself by trying to find some part of the thing you can get a grasp of.
Most complicated seeming things (especially in tech) aren't really that complicated "to get". You just have to know a lot of stuff that the thing builds on.
