Yup, we see posts about this from time to time, its been happening for years, but a reminder every once in a while might prevent someone from having the issue.
A useful reminder to have, thanks.
Does anyone know what about the laser actually kills the sensor?
The energy transported with the LASER light is converted into heat if the light is absorbed by the chip. The heat might damage the structures on the chip consisting of the pixel structure and conducting signal lines.
The problem with movie mode and live view is that the chip is alltimes exposed to the light. If the image of a light source is intense enough you might heat up the chip structures to temperatures above spec. This might be around 100 degree Celsius.
LASERs are monochromatic and the light bundle is nearly parallel. The light is focused to one tiny spot - 1/1000 mm is possible - with a single lens, more with a well corrected lens. If the thermal energy cannot be removed by thermal conduction in the chip to the back or outer regions you have some pile up of thermal energy which means increased temperatures. The tiny structures made of different materials/material combinations mix by diffusion of atoms due to the heat.
With blue light there might be another effect: Blue light consists of photons with higher energy per photon and these photons can damage structures directly - think about ultraviolett radiation which has again more energy per photon (=light quantum) and might damage biomolecules resulting in cancer generation!
If I have the sun in the frame I try to use the diaphragm control button to reduce the heat load on the sensor - this is one possible measure to reduce heat/high temperatures on sensor regions.