Or at least heated headlamp housings, which may be more practical, only firing up with the windshield wipers or heated mirrors. There are many high-KT plastics, I use some in my business, although I don't know if any are clear enough to use as a headlamp lens.
I tried all LED's in my lamp posts, and had the same problem, they'd be completely frosted over most winter nights. Since each holds three bulbs, I switched to running 2xLED and 1xIncandescant, to provide just enough heat to keep the glass clear. Works pretty well, and keeps the advantages of lower power usage and less frequent bulb changes (in theory) of LED's.
I'm an EE, and have been working with LED's for 40 years. But the household LED light assemblies have been very hit or miss on internal circuitry failure rates. I've had many that don't last as long as a typical incandescent, then others that have been running more than a decade, with no sign of ending. If properly designed, their MTTF should be around 1M hours = 100+ years of 24/7 use... basically the socket or plastic shell should corrode, before the electronics fail. But in commercial electronics, it's all about budget and cost, and stupid component or design decisions are often made to shave pennies.