What?
The isometric look was one of the main (if not the main) selling points in the Kickstarter.
The amount of detail in the environment is simply not the same as what you get with 3D.
Maybe the isometric was a selling point not because they wanted to make it isometric, but because they had no choice.
Think about it, given the amount of logical cut scenes you would have. The riots in the city, the wagons at the beginning of the game, the biawic, even Grieving Mother's story line. Is there any possible way that they could have created those cut scenes, plus the voice acting, and the larger, more detailed, 3D graphics on a 3 Million dollar budget?
No, they would need at least ten times that. So maybe they went isometric because if they went the other way the budget would be increased ten fold and no kickstarter campaign would ever realistically meet a 30 million dollar goal. Perhaps that was the bigger motivation in going isometric vs 3D, money, not artistic design.
And those machines you see in the game can easily be done in 3D. The meshes might be slightly harder to deal with and the textures would be far far larger leading to more time to make them and computational power to handle them as well as an increase in cost. But it could be done, if Obsidian had a budget about 10 times what this was.