“MTBF in decades” is marketing fiction. The diode itself might last forever in a lab, but the driver electronics, thermal paste, seals, and optics sure don’t. Real-world LED headlights die from heat cycling, moisture ingress, and driver board failure long before the diode hits its theoretical limit. Most assemblies don’t even have a serviceable “bulb” to replace. Pretending you can just pop in a $40 LED chip instead of the $900 housing is wishful thinking.