There is no doubt that it is better for the vehicle to have the car in neutral at the light. The release brg and PP will have a longer life. Pressure plates are fairly robust, (as are release bearings) but I have had release bearings fail on me in the past, well before the clutch itself wore out. I believe it was from poor handling of the bearing before it was installed but still…
Now, is it better to keep it in gear in case of an emergency? Well, thats up to you. I wouldn’t bother and never have. An experienced driver will wait at the light with his hand on the stick and foot close to the clutch anyhow. While it would take a slightly longer time to put the car in gear and release the clutch, if your any good the time difference would be minimal, IMHO.