The outside of the lamp fixture reads 88 f. So if the snake did decide to "coil around it" it would actually be at the appropriate temperature for prolonged contact. When operating a heat source at a max temperature of 180 f you run significantly less risk than as you said running at 500f.
As to the problem im solving its people who use ches and set them on top or inside of an enclosure running at full power. Which people do at risk to their animals. This is a much safer alternative when placed on top of a cage as it wont burn the snake.
If you place your holes close enough and you have wire thats easily malleable ( combined with the fact that the light would be hanging several feet off the floor makes it hard for me to see that happening . But you have to watch and monitor as will all things.
No one is telling you to use this. Or what to do with it. Its a DIY forum where people post things they made. Where other people can use all part or none of the idea.
Instead of trying to bring other peoples ideas down you should figure out a better one.