After thinking about it I think it may be there to keep rodents out rather than protect against road hazards. Just reach in and flex it and you'll see there's not much to it. I decided to repair mine with a pair of black zip ties. It's not visible at all so no need to get fancy.

I ran the engine until the fans came on to verify that all is well. I didn't realize the fans reverse the normal flow and blow air forward. Never noticed that when sitting in traffic.