Well, we could argue till the cows come home, I swear by the stuff - but yes it does collect dust I've seen plenty of boards in wooly jumpers, it can carbonise in high temperatures / voltages, and it is worse than useless on printer guide rails, however SILICONES are HORRIBLE things anywhere near electrical bits, there were tests done a few years ago, where they found silicones crept for inches along wires until they came to a switch or relay contact whereupon they sat on the end of the contact and turned into rock spikes in the little arc.
I never lard the stuff on unless using it for it's almost original purpose, and have found it to be somewhere between pretty benign and really good... but I'll have to do an investigation into the official line on recommended contact lubricants.
I also have to concede that I am a fairly old timer!:blush: