Remember that the core problem here is the tension that arises when people say that ineffective charity is impermissible while also saying that selfishness is permissible. This pair of views implies that a more beneficial option is more blameworthy, which seems paradoxical. But if we say that both of these options are impermissible, the problem goes away: the more beneficial option is never more blameworthy than the less beneficial option.
Remember that the core problem here is the tension that arises when people say that ineffective charity is impermissible while also saying that selfishness is permissible. This pair of views implies that a more beneficial option is more blameworthy, which seems paradoxical. But if we say that both of these options are impermissible, the problem goes away: the more beneficial option is never more blameworthy than the less beneficial option.