I'm a bald dude so to prevent helmet line sunburn when riding I wear what I call a helmet liner - but it's basically just a sweatband / beanie combo made of a stretchy material similar to what bib shorts are made of. There's a bunch of brands out there and I use them all. Headsweats, Halo, a few no-name amazon ones, various others. When the wind temp gets down below about 60F, my ears hurt pretty bad. I pull the sweatband part down over my ears in these cases and it mostly stops the ear pain. Like how you'd wear a winter beanie. Below about 55F and I have to wear an actual fleece lined beanie under my helmet because the ear pain would otherwise be unbearable.
I have no issues with hearing traffic and other environmental awareness issues wearing these beanies. The cat ears thing seems like a solution in search of a problem but if people like it I can't knock it.