These "pointless" (but not really) dependencies we're talking about are the same as useful ones, but instead of weighing the cost against a more direct benefit

These "pointless" (but not really) dependencies we're talking about are the same as useful ones, but instead of weighing the cost against a more direct benefit (whatever the library gives), you're weighing it against these more indirect benefits, which is much harder. Facades and the various "layer" style abstractions aren't pointless. The whole point is to add a layer of indirection, for the benefit of being able to switch out underlying dependencies. The whole point is to make it easy to migrate off of a dependency.