Is there a meaningful distinction to be made between the system and the content?

[kyoryu]

Really? If I stab someone in the kidneys, or throw a sharpened cream cheese spreader and hit someone in the head, I can't kill them in GURPS?

Kidney stabbing is possible, for sure. These things are just all fairly low probabilities. GURPS has a reputation of being deadlier than it is.

Again, some of the high tech stuff changes that, especially on a lucky roll. At high tech levels, GURPS starts to get pretty binary - you're either fine or a thin red paste.