If you use the custom option "Truncate very large signatures" then it hides most of it, like this:
(
Click here to toggle those options)
I don't know if this signature is worth being a policy nanny over. There are a couple options that either partially hide it or hide all signatures, or the ignore feature which totally hides everything (including posts).
Although @ Grumps, I'm disappointed after all this time you are still using the same low-resolution pixelated image. I feel like if you're going to subject us all to scantly clad Christmas women you might as well change it up every once in a while.