Timmy does play with a murder doll - it's called 'gaming' - most of which are geared around either fighting or murder. The question about whether or not playing war based games does create sociopathic tendencies in children or adults is still up for grabs.

I worked at the sharp end of child protection - so I'd take a pragmatic approach to this rather than a speculative one. Any solution which results in a net drop in abuse to children, doesn't punish people seeking not to offend, doesn't infringe of bodily autonomy and/or can be shown to work with careful analysis and rigorous testing is fine by me. I'm not sure sex dolls are the answer but I'd want to see some serious evidence either way before I threw my opinion one way or the other.

On a separate note, you might enjoy a play called 'The Nether' written by a US Playwright called Jennifer Haley- it deals with a whole bunch of moral complexities and their solutions. Well worth a read if you get a chance.