To complete (me) a riveted connection is the special case that can be either treated in multi-body sheet metal or in assembly. The sheet metal with multiple thicknesses seems to me to be exposed to a lot of errors (parameterization by exception so risk of forgetting) and should therefore be the exception.
@Olivier42: I prefer a controlled and manageable external reference (you just have to cut the cord at the right time) than a stack of functions that will have to be taken over (even if it's only the sketch plans) to separate the pieces to put them in plan.
I'm not trying to convince anyone, but on the other hand to say that there is only one method, in a case where there are 2 (or more...), I want to say it "no there is not only one".
Both approaches remain perfectly valid,
Working only with external references is not a generality, of course the software allows it, but you have to know the consequences, to know what you are facing afterwards.
If people then "prefer" to work only with external references, it is their choice, it is not a generality.
Working in a PRT-multibody-sheet metal is not "creating more problems"...
In some cases, one method-based approach will be more suitable, and in other cases it will be the other.
We don't all work in the same industry, and we don't necessarily make the same type of parts, so the needs can vary, and so can the approaches-methods.
Another great benefit of using a multi-body PRT "sometimes":
the "add weld" function which allows you to create a 3D line footprint quickly (and a weld table if necessary), and above all allows you not to be fooled during assembly (with other parts, screws, etc...) and come across the famous :
It doesn't work because of the welding, you'll have to grind...