Well, you were the one who said it was a cop-out. Are you not of that opinion any more?
IMO, the culpability of the manufacturer should be zero for general purpose tools. For things like guns/weapons, which were invented solely for killing living things, you can make an argument for regulation...
>The fact is some people think use/trading of certain financial tools should be illegal and that those who caused problems with them should be held responsible.
I don't think its right to base any argument simply on what "some people" think. Why not instead, list the pros and cons of the tool, and what you would change?