kinda makes me believe that they sliped into bad habits
Very possible, it could be bad habit that cause it. If found early in gingivitis stage, only scaling (plaque removing) and rooting (smoothing) that makes the gum reattach to the teeth is a good option, it can even be effective against early stage of periodontitis.
And at any stage it is, I think seeing a dentist could help, it is treatable.
In addition to the disease, if not taking care of by scaling and rooting after noticing receding gum, no amount of brushing can heal the disease. That is why dentist intervention is needed.