It is misinformation. Masks (cloth or otherwise) were meant to reduce infectiousness, not completely prevent the possibility of infection. Masks (cloth or otherwise) do in fact reduce infectiousness. The misinformation is the implication that masks are pointless because you can still get infected. The point of masks is to get the probability of spreading it down by some multiple, not to be a personal not-my-problem-anymore pass.
This is like saying seat belts don't work because you can still die in a crash.
This is like saying seat belts don't work because you can still die in a crash.