Is someone more knowledgeable "better"? Sure. But sometimes it's about getting a specific thing done, and if you're hiring someone to improve a web thing that uses React, maybe you don't need someone who understands compilers and the kernel and how the underlying hardware works and all that. Maybe you can spend a bit less and get someone who will do a perfectly adequate job.
For example:
If you build computers, you should understand how the individual components are implemented.
If you build computer components, you should understand materials science and electromagnetism.
If you study electromagnetism, you should understand quantum mechanics and relativity.
Firstly, React is not compiled. Secondly the graph or tree or whichever aspect can come naturally when you come up with the idea of how it would be best to maintain JS apps.
In fact most important experience should have been grinding put tons of unmaintainable JS apps to come up with something like that.
And tools are best used when they are understood.