With the older ones they have step entry of events but aren’t step sequencers.
Typical workflow is playing stuff in from pads or keyboard.
With a step sequencer typical workflow is switching on/off gates with a row of buttons and setting pitch,etc with knobs or sliders.
I wouldn’t call the MPC a step sequencer even though it has step entry, Just like I wouldn't call Logic or Cubase step sequencers just because they have some step sequencing features They are the furthest thing from peoples minds when they ask for a step sequencer.