When the pivots on a diaphragm spring wear they can wear unevenly. That means that the travel of the release bearing needed to pull the pressure plate all the way off the disc may be longer than the cable can provide even with no free play at the lever. If you have no free play now, and the disc isn't released with a full travel of the pedal, it's the clutch. Might be a bent release lever, but that still means removing the trans, and if you do that, you'll remove the clutch.
There are lots of ways clutches wear. You mentioned a couple. This is another one.