Wonder what the replacement cost is for one of them? I had to replace the hid assembly in my old lincoln ls due to a crack and the msrp was almost $1K!
When we got the RX400h (one of the first to use the pivoting lenses), we were told that if we wanted to write off the car, hit a wall at 5mph - it'd crack the headlamps, which were $9k each to replace. That was from the dealer, which is not a reputable source, and I'm sure the costs have come down significantly (especially with them becoming available from scrapped cars) - but yes, better technology costs more to replace.
A quick look on ebay is showing them at about $350 each - and bulbs are 2 for $29.95...so I don't see HIDs as all that expensive (assuming you don't encounter ridiculous dealership mark-ups).
In any event, I'm all for better tech - LEDs have amazing capabilities, and if they're being under-engineered (using more energy than xenon bulbs, not lasting more than 10 years, etc), then it's something to do with the manufacturers cheaping out...not the tech breaking bad.
My diving torches are both LEDs. I use the Princeton Tec Torrent LED. It started as a Xenon, then LED, and now improved LED. All use the same batteries (8AA) and the same construction.
1) Xenon - 115 lumens; 8 hrs of burn (
http://www.karstsports.com/prtectoxe.html#.Ulf64dLrw2Q)
2) LED (1st) - 126 lumens; 30 hrs of burn (
http://www.leisurepro.com/1/2/12553-princeton-tec-126-lumens-torrent-led-dive-light-black.html)
3) LED (2nd) - 280 lumens; 30 hrs of burn (
http://www.leisurepro.com/p-ptctl/princeton-tec-280-lumens-torrent-led-dive-light)
So between the 2nd and 3rd, same flashlight, same everything, but they got more than double the light output with no increase in battery consumption. If any of the car LEDs mentioned here aren't performing well, it's because they're not designed to - not that they're not capable of it.