No, but yes.
At the moment, the games story is linear in archipelago region. Then it offers great freedom to do what you like and in which order in general. There are some small dependencies for some missions that make them linear in a limited frame.
What I would like to see is, as the game evolves, that it gets splitted into chapters. Let’s say, the story in total is linear, but the way isn’t.
And these chapters may end or start with some more storytelling elements, like the introduction of the game if you start a new playthrough, a cutscene or the players character talking to him/herself… Or a storyteller that tells us some words.
For example, imagine a mission that ends a chapter… Now in the next chapter the soviet landfall starts. This could be introduced by something like the Landfall-Trailer. Maybe additional a text “2 weeks later…”.
Something like with the introduction of the firebirds, where you meet them and fight them numerous times before there is a mission that introduces them, should be avoided. Such logical gaps, to say it short.