I think the OP asks a great question.
As a data point, I compared the Kuzma Safir to the Kuzma 4 point 11 on a Stabi R turntable, in the process of deciding whether or not to buy the former. I understand @lewm’s caveat that you can only ever get partial results due to the need to match tonearms with appropriate cartridges. So, I brought my 4 point with a Zyx Universe Optimum, well broken in, and adjusted it with an Acoustical Systems Smartractor. Dealer had the Safir with an MSL Gold. We swapped the tonearms and listened to the same LPs.
To me (and him, the salesman) the results were not subtle. The Safir/MSL was clearly superior to the 4 point/Zyx Optimum. I believe it was a difference that anyone would hear. The immediate sensation was of moving from a small street to a broad avenue of sound. Just more, wider, deeper, more detailed, better timbre, more relaxed, more dynamic, etc. A notable sensation in the bass was the sustain: acoustic bass notes just lingered and rang much longer than I had heard before. this struck me because up til then, the Zyx Uni had the best bass of any cartridge I had heard. I doubt this was the difference between these two, high level cartridges. my sense, after this experiment, was that I had really underestimated the importance of a good tonearm. (I bought the Safir).
