Like most dramas, the conflict that would easily be solved if people just F#$@ING talked to each other. So of course the most logical thing to do is not that. There wouldn't be a story otherwise.
The way I understand it, "drama" is 90% dialogue based conflict, with maybe a 10% chance for some action conflict. The opposite is "Thriller" 90% action conflict with a 10% chance for some deepet dialog conflict than just what is said in the physical confrontations.
In drama, nearly every problem is stemmed from some key focal point of action/inaction that causes the cast to then bicker, argue, take sides, keep secrets about, debate, and possibly even briefly fight over everything related for the rest of the series. Yet it could almost if not always be solved with just the main cast having a cordial, non-threatening, non-aggressive, and non-restrictive sharing of information. Leave all of their wild emotions behind at the door, and just share the facts of the matter.
In Thriller, everything tends to stem from a misunderstanding or lack of information about a key focal point. Playing heavily into the unknown "whys" and "hows", but mainly using action to figure it out. And yet, it usually can almost always be solved with some form of basic level of competency that the main cast somehow lacks. "Oh, is that a dark room with only the occasional lightning flashes to light it up? Better use my flickering flashlight that is nearly out of batteries instead of just flipping on the light switch." "Oh, a seemingly abandoned factory in the middle of nowhere that doesn't seem to be nearly as abandoned as it should be? And is that something highly dangerous and possibly illegal going on? Aren't those armed guards too? I see no reason to report this to anyone. Its best that I break in using the broken side window on the second floor that I have to climb up a pile of rubble to reach. Then I absolutely must jump inside knowing I cannot make it back out using this way so that I can take a look around all by my unarmed myself. Its a good thing they left the lights off though. Who needs proper lighting to work, right?"
The funny thing here is that in both generas, the majority of the main and supporting cast is usually a part of both groups. They are both dumb, and don't share important information when it is obvious that they should. Only someone in the main protagonist's group can be allowed to break out of this too, and even the chances of that is a minor rarity, and often done on the heels of a grand, but obvious, epiphany of all things.
And you are 100% right. There wouldn't be a story, specifically here, if this were not the case. If it were the case, then this story wouldn't be a drama. Its genera would then be either of "mystery/romance", where everyone is open and sharing important information all the time, or "action/adventure", where the cast is capable of using general comon sense right from the start and goes in coordinated with guns (or bows i guess) blazing to fight the common enemy.
Its why the FL is so entertaining. She is done dealing with bullshit, and knows when something is worth sharing/doing. She is strong enough to handle it, and isn't stupid enough to not share crucial information to those who need to know, without thinking it through about all the pros and cons of doing so. But its the system instead that is forcing her to act in certain ways that go against her ability to break out of that common role.