Only in a case where the listener feels it will be of benefit to him as stated in MC that the BMC is on. This is the case where it needs to be toeles for the listener. If it wasn't spoken litoeles then one may not listen even if there is toeles for the listener.
That’s talking about real gnai. In is case where it isn’t gnai, it’s only because it’s damaging, than if the reason why it isn’t ltoeles for you is bec you can’t be part of that, that would mean essentially that it isn’t LH for you.