Why is academic writing so complex?

I am facing the giant task of developing my research thesis and if I said it was easy, I would be lying through my teeth. People tell you to just write but no one tells you what you need to write or how to write it but you are expected to communicate with the community of practice. what is someone to do?

In addition to the writing challenge are other key questions related to the topic; why is this topic important, for whom is it important and why should we care? Your professor tells you what new knowledge are you creating or what gap are you solving? You take a 3 month hiatus to go and think and you are like, to hell with PhD.

Why are there few lessons or training on how to write academically? How to read, when one is expected to read a lot and synthesise whatever they read?

Just know yours truly is suffering.