This was interesting as I had wondered whether Terence Tao realized that the Navier-Stokes Millenium Prize problem was kinda useless from a fluid dynamics application perspective. Turns out that he does!

> While the equations do come from a very natural physical motivation - the study of incompressible fluids - the regularity problem is not important for its direct physical application. [...]

I disagree that the Millenium Prize problem would tend to "spur further development of the field". I'm not seeing that. The people working on the Millenium Prize problem aren't helping solve more practical problems like making better turbulence models. I wish we had more people of Tao's caliber working directly on turbulence modeling! Indirect work won't cut it here. In my view, the Millenium Prize problem has mostly been a distraction from more important issues.