Of course the Khumbu ice fall has many ladders, that typically have to be placed anew each season as the ice moves. So one more ladder is no big deal IMO.
I agree with Viesturs. (And I expect most experienced mountaineers would also.)
It is not just the number of ladders--the locations are also very important. The ladders in the ice fall are there to make the passage between basecamp and the Western Cwm safer--crossing the ice fall is generally more dangerous than hard and a disproportionate number of the deaths occur here. The Sherpas (working as hired porters) also take the majority of the risk here--they have to pass many times to ferry supplies up to the higher camps. In contrast, the Hillary Step is one of the signature technical difficulties of the South Col route. Bypassing it with a ladder will downgrade the climb and downgrade anyone's achievement in summiting.
Bypassing the Step is an aid to the commercial expedition companies (anything that makes it easier is likely to bring them more business...), but as Viesturs notes, it is not likely to alleviate the congestion. (Much of the upper part of the route is basically single file.)
Should we close the airport at Lukla because Hillary and Tenzing had to walk from Jiri?
The Lukla airport serves far more than just Everest Climbers. The previous 2 week walk-in also served to get the climbers fit, build some altitude acclimatization, and build a team.
Why don't they just drill a railroad tunnel to the summit? It would avoid the steep climbs, the falling rock and ice, the storms, crevasses, and all sorts of other risks and impediments...
Doug