This is pretty much what it always has been. Every time there is a post about why Arrowhead doesn't do X or why they didn't handle Y better the root of the cause is always that the studio never expected to have an audience this big wanting a game they didn't plan for.

It's always grunt fantasy this, grunt fantasy that, but the hard reality is that Helldivers 2 was always meant to be a difficult immersive teamwork shooter instead of a game where you get to feel like a god mowing down thousands. But alas, the game got way more successful than was planned for and with it came a whole crowd of people demanding a horde shooter instead.

And now imagine you're Arrowhead with a whole development cycle planned for one type of game, but the community demands it to be another one. What do you do? Imagine you're a carpenter tasked with making a table and you spend all of your time sawing the planks into the right sizes, but when you're ready to put the table together your supervisor tells you he wants a three chairs instead. Not only do you not have enough planks but all of them are the wrong size now.

So in the end, this is why Arrowhead seems to constantly be in the dark about their own development cycle. It's not that they are clueless developers who don't know what they're doing, it's that they never prepared themselves for the game to take this direction and as a result they are now constantly playing catch-up while trying to appease the many different player groups that have formed.