The game is very much like chess. There are pieces on a board with movement and abilities. You can use your pieces to defeat the other pieces, or you can be defeated in turn.
The problem isn't the analogy of chess to bg3. The problem is the AI in bg3. If the AI in bg3 could learn and adapt to the players tactics then it would become one of the greatest tactical games in the modern era.
Unfortunately, the AI is static.
Let me add to this a bit.
In chess, the AI is designed to win, to beat you. That's the goal.
In BG3, the AI isn't designed to beat you. It's designed for you to win. The only question is "how hard is it supposed to be for you to win?"
When I ask for a harder mode in the game, what I want is a game where the rules are the same for both sides and the AI is designed to beat you, to win. That way I'm going up against a real challenge.