So: I ordered a tube for my Threadripper for the first time. 1 gr. tube is already very scarce in terms of content. With the spatula supplied, you can just about cover the surface with a thin layer. After that, the tube is empty.
No, thermal paste does not have an "insulating" effect until the heat sink is mounted correctly. The mounting pressure is not supported by strong backplates for nothing, which pushes any excess cooling paste out of the gap. So you only have the disadvantage of a completely smeared motherboard. It should be noted that the excess may drip down onto the GPU after a while, but this is less essential.
I agree with the video from the first answer, 10 CPUs might be a bit exaggerated, but a whole tube even for Threadripper is definitely WRONG. Sorry guys, you're welcome to do it this way, but I want a clean motherboard :)
You can hardly go wrong fortunately, thermal paste doesn't conduct electricity as long as it's not metallic. It only fills the few air holes between the CPU and the cooler.
For normal CPUs, please don't spread the paste with a spatula, that's really not necessary and only wastes the paste anyway.
If you put too much paste on it, it is no longer conductive but insulating and the CPU gets warmer or even overheated. Just put a dab in the middle of the CPU and apply it evenly, the paste will spread evenly.