What Is the Linguistic Cortex?

Linguistic cortex is part of our brain that chooses words and formulates how to say them. But thoughts are not restricted to the linguistic cortex, right? For example, we have default mode network which gives us capacity to self-reflect. And when we speak, all that crap has to get channelled through the linguistic cortex. So why do we assume that communication is different? Why do we assume just because we can think, one thing, i can think in ninja moves or matrix martial art sequences, but that doesn't mean my body can do them?"