[whyoh]

Anecdotal, but even with the new fans, stamped out grills still perform poorly in terms of noise. They're popular because they're cheap.

I'd gladly pay $10 more for a PC case with a less noisy grill, but I can't find any that has this, not even ones that are advertised as "silent".

[rtkwe]

It's a pretty easy mod if you really want to swap to wire grills. 10 minutes with a dremel and 10 more to make it look ok again and you can have a completely open fan mount.

[fomine3]

I did it for honeycomb grill with metal scissors, and replaced to cheap metal wire ring grille. It significantly reduces noise.