I don't think Dungeondraft maps look bad by any means. I have both Foundry and Talespire, and while I agree that Talespire is very pretty, a 2D map in Foundry is more than acceptable.
The problem Talespire faces is that it does so much less than Foundry. It's like comparing MS Paint to Photoshop. A visually gorgeous MS Paint, don't get me wrong, but one with only a bare minimum of tooling.
I also get the impression that Talespire's future scope is mostly limited to visualisation. It's not aiming to provide character sheets for a hundred different systems, or automate hit and damage rolls, or provide shop and inventory interfaces, or visual-novel style character popups, or drag-and-drop NPC design, or any of the other thousand things you can get a Foundry module for.