Sync phases behaviour with app of apps

[abdoofathy95]

So I was wondering about the behaviour of argocd presync hooks when it's combined with app of apps. so let's say we have 3 levels, and on the root we have a presync hook, will that hook be triggered if an app on the 3rd level was synced ? or is there is application isolation ?
if the hook on the root level won't be triggered by a change on an application on the 2nd or the 3rd level, is this because of some kind of application isolation ?