I guess it is a common downfall for stronger entities to understand less of their situation.
Kongou may be the most advanced battleship that ever faced Iona and the rest of the Blue Fleet but she sucked so bad in adapting to her circumstance. Her persistent ideals on “what” a weapon “should be” took the better of her, resulting in her loss of this battle.
It’s not that Kongou lacked tactics but rather, she wasn’t able to formulate new ones that would counter Gunzou’s strategy. And the reason why she couldn’t do so was that she never understood him or try to understand him in the first place. After all, you can never counter something if you don’t understand how it works.
What I didn’t expect though was the cliffhanger at the end. Could I-400 and I-402’s ambush have come from a directive much higher than Kongou? It doesn’t look like she’s aware of what happened after Iona made her escape so a much greater boss may be appearing as this season draws to a close.