is it a common ocurrence on Linux that you have to constantly mess with the settings and end up in an obscure rabbithole? that's why I haven't given it a go.
No, you absolutely don't need to care at all about the memory management when using Linux. This rabbit hole is really only relevant when you want to work on the Linux kernel or do some really low-level programming.
I would say the most obscure thing that is useful to know for running Linux is drive partitioning, but modern installers give you a lot of handrails in this process.
No, not really. This is from the perspective of a developer/engineer, not an end user. I spent 6 months trying to make $product from $company both cheaper and more robust.
In car terms, you don't have to optimize or even be aware of the injection timings just to drive your car around.
Æcktshually, Windows or any other OS would have similar issues, because the underlying computer science problems are probably practically impossible to solve in an optimal way.