Tephra
10
You say that with sarcastic wording, but what you say is exactly correct. A new map is the most expensive addition they could do to the game (except maybe upgrading to UE5), and they would need to be able to recoup that cost.
Siptah did not sell super well, and I suspect Funcom never made back their investment on it, or at least failed to meet their expected profit, possibly contributing to their later decision to move away from the DLC model to microtransactions.
A new map is not likely due to the cost, further diluting the player base, and because it would not fit into the current monetization model.
Crowdfunding is also not a very likely possibility. I doubt they would be able to raise enough and would look super greedy in the process.