Adjusting for tire wear or driving characteristics?

I hear a few conflicting views regarding tire setup.

Many people say you should have even wear and temps across each tire, outer, middle, and inner, and to get this by adjusting camber and tire pressures appropriately.

On the other hand, when I get other people's setups in game, most of the time it appears that the tire temperatures and wear are very imbalanced, with the tire appearing to be running way over or underinflated, as well as having uneven tire wear as a result of extreme camber.

What exactly am I aiming for? Is setup purely about driving feel, or is there real objective performance to gained by optimizing tire wear?