Careful about saying people disgust you. There are pretty clear rules about being civil on this forum.
That said, there’s merit to both systems.
Bionics having weight means that strength directly affects how many bionics a person can practically have which, I think, is a good thing. A larger person with more muscle mass does have more actual volume within which to store bionics. You could still have a similar system for a point limit, that more strength gives you more points, as could mutations like large and huge, or having a tail or extra body parts.
There’s also something to be said for the fact that we don’t know how much space a bionic might take up, and there’s room for some infrastructure to be common, e.g targeting system bionic, telescopic eyes, and infrared vision. Those all involve replacing or enhancing the eye with cameras, so they could all share a great deal of actual space. Whether we actually want to have things like that for game balance reasons is another matter, but I think using a system with no hard caps, only soft limits, would be a good idea.
Perhaps both, you get a certain number of “free” installation points, beyond that anything new added to an area has weight and encumbrance penalties.