What is the difference between real periodontal pockets from false ones?

Bone loss: "real" pockets are due to bone loss and subsequent loss of the attachment complex on the root surface. Pseudopockets are caused by hyperinflammed gum tissue, the is swollen and bleeds but no bone loss is involved. Psuedopockets can be just a tender to clean as "real ones" and may require local anesthesia for a thorough cleaning.

It's complicated: To simplify a complicated issue, false pockets are due to poor position of the teeth in relation to the gingiva. Or they could be caused by slight inflammation. "real" periodontal pockets represent areas of bone loss and loss of tooth support due to chronic infection and inflammation, and this condition demands treatment. A prudent dentist/periodontist can easily distinguish the two types.

Pseudopockets : Pocketing occurs when there is inflammatory destruction of the supporting tissues of the tooth....Connective tissue and bone. Pseudopockets are areas of increased probing depth with no tissue destruction, e.g. Spaces between crooked teeth, hypertrophic gums due to medications, incomplete eruption of gums "gummy smiles", and healing after wisdom tooth removal are some examples.