The reality which you describe is that of the developer.
But the user's reality may be quite different.
They were expecting an improved stair tool, not a new stair tool.
In the long run, the new stair may prove to be better for them, but the reality is that this remains to be determined.
In the short run, the users may have real dissappointments due to ufullfilled expectations and real logistical headaches due to the existence of multiple stair object types.
As an aside, being able to inherit vectorworks object types from existing vectorworks objects could be a real boon to development...and potentially avoid this sort of issue in a really cool way.