The thing about modern terrorist operations is they aren’t a top-down pyramid where you remove a few blocks and the whole structure collapses. They’re like a hologram where no matter how small you slice it, what you’ve got in your hand can be used to reproduce the entire structure. Terrorism is a reaction to whatever the situation is on the ground, even if that situation is completely in the mind of the viewer. As long as one person remains, and that person has not been convinced to see the world differently than the entire structure will likely reemerge later under a different guise.
Nonetheless the organizational structure recruits followers. When that structure fails recruitment fails.
Certainly the sentiment remains in the hearts and minds of some. Without adequate support little happens.
Starving terrorist organizations is the key to their effective demise.