I’m not sure if I understand your question but what you should realise is that Revit knows everything about every parameter in every element in the model, immediately.
Every time you add, delete, change anything Revit knows about it. That’s the “I” in BIM.
A schedule is then just a special type of view which shows you the data rather than the geometry.
You could have one multi-category schedule for every item in the model - it wouldn’t be very helpful though because it could only use the fields which are common to every element category e.g. Mark, Comments, Description etc. It can have a Count field but there is no Length field, so it could include the quantity of pipes or ducts or conduits but not their linear length.
So to make your schedules more useful you filter them - first by Category, then more parameter fields will appear which are specific to that Category. Then you can filter/sort further using the parameters, e.g. by Level, by System etc etc.
You can add custom parameters to give you more filtering/sorting control for example a code for different sectors of the building.
Whatever way you cut it though the data in every schedule in the model is the same data, you are just looking at it from a different perspective.
Not sure if that helps.
