Comment by lexszero_

And part of the reason for that is compatibility with existing light fixtures using legacy sockets designed 150 years ago at the dawn of electrification for incandescent bulbs, where the part dissipating the most heat was the light emitting element itself, and not whatever lays between it and the mains power source. If the customer doesn't want to pay for a slightly more expensive LED lightbulb, they sure as hell won't pay for a whole new fixture specifically designed around LED technology that will last forever.

This is anecdata, but I haven't replaced a single LED bulb since I bought the current set ~7 years ago, and it's nothing fancy, just basic IKEA stuff.