It's not that bad.
Sea walker "dives" are normally done at the same place every single day. Popular places for sea walkers are often reefs with shallow water, some hard corals, lots of sand and rubble.
Damage is limited to a fairly small area.
Scuba divers inflict imo quite a bit more damage to the reefs than a relatively small number of sea-walkers in a relatively small area somewhere off a beach on a hard coral reef.
Maybe we should start another thread about this subject and get out of this coral-bleaching thread....