The capacity of the strut and node in the STM depends on the dimensions of the support and loading plates; however, these values are not provided in most of the literature.
Your question is interesting. It is like that, as you affirm. The resistant capacity depends on the dimensions of the support or the load plate. Those dimensions can be variable. For example, if the dimensions of the plate are very small, local failure may occur at the support site. I recommend the following article. I hope I can help.