You say that the BionicMobileAssistant, with its ability to move, is not just a type of Festo Bionic Handling Assistant which is fixed, highlighting the crucial difference of mobility, and I agree that mobility should not be underestimated, but this classification could be viewed differently.
Considering mobile as a simple "addition" to the fixed one ignores the fundamental transformation in usage and accessibility that it represents.
For example, in Senegal, a Mobile Money service that moves through remote villages is not just an "evolution" of a bank counter; it makes the service accessible to those who were deprived of it.
Hierarchy is only stable if mobility is considered a secondary characteristic, which, in real life, is completely false.