speaking of navigation, should something like this work?

@Composable
fun BasicNav() {
    var isLoggedIn by remember { mutableStateOf(false) }
    NavHost(startDestination = "Profile") {
        composable("Profile") { Profile(isLoggedIn) { isLoggedIn = !isLoggedIn } }
        composable("Dashboard") { Dashboard() }
        if (isLoggedIn) {
            composable("Scrollable") { Scrollable() }
        }
    }
}

(the lambda passed into

Profile()

) is just connected to a

Button

to toggle the logged in state

This sounds suspiciously like the same issue mentioned here: https://kotlinlang.slack.com/archives/CJLTWPH7S/p1601232258162100?thread_ts=1601232258.162100&cid=CJLTWPH7S

yeah it is. lifting the state up to a higher level made the conditional navigation graph work.