I think a parallel can be drawn between Islam and violence and Christianity and slavery in the US in the 1800s.
Broadly speaking, half the Christians in the US believed the Bible supported slavery and the other half didn’t. I suspect that the number of slave owners in the South were in the minority. But the number of people who lived in the south and who also approved of or tolerated slavery was much greater. So slavery in the south continued.
Is this the case with violent Islam? Certainly there are only a minority of Muslims committing atrocities. But are those living alongside them tolerating (or approving) the actions of their violent neighbours in a similar way to the southern Christians tolerating slavery?
Eventually the slavery issue was sorted out within the ‘family’ with the north defeating the south and imposing their Biblical understanding. This is where there needs to be a groundswell of vocal and high level support by Muslims for ‘peaceful Islam’ if there is to be any real change. Solutions are not going to come from outside their family. This is the only way I can see of solving this problem.
But if Islam is inherently flawed then the likelihood of eliminating this violence is low.
I would argue that the Christian scriptures (ie the NT) did indeed support freedom for slaves. Hence the truth won out over error and the slaves were liberated from Christians by other Christians.