A wall without a recovery move is as useless as your friend claims. Bronzong, I'm looking at you. However, Skarmory, Hippowdon, Blissey, and Cresselia (who is defensive enough to survive 3 turns of Rest/Sleep Talk) can come in on something they're supposed to wall, damage/paralyze/poison/sleep whatever the opponent switches into them or set up some other type of support move, then recover off the damage they've taken when it's safe.
My special wall is Tentacruel, who rapid spins and sets up T-Spikes. Forretress is a similar wall who is also quite useful. I have sucessfully used Garchomp as a wall with Stealth Rocks.
Bronzong would work, except I have a fire weak on my team and never really found a use for him. Nonetheless, he has hypnosis, reflect, light screen and only a single weakness. I wouldn't call him useless at all.