...Additionally Musk has already mentioned many times that there will be a HW 5 in the future, indicating that HW 5 will be necessary for FSD. ...
Logically and technologically speaking, this conclusion doesn't follow at all.
Note that when Elon made this mention of HW5, he specifically and preemptively refuted the conclusion that FSD would not operate on HW3 or HW4. In fact, the very reason he brought it up was to combat the idea that a new hardware generation automatically represents the death knell of existing hardware capability.
You are free to disbelieve him, but it's only fair to include his own explanation while you're citing the fact that he acknowledged an HW5 would come someday.
Aside from that, we are all more than familiar with the inexorable march of hardware. New computers, consumer electronics and so on, constantly evolve their hardware platforms without necessarily obsoletting or halting the development of software that continues to run on prior hardware.
As many have pointed out in these discussions before, at some point, two or three years after the introduction of a particular hardware generation, it becomes difficult and expensive to continue supporting and shipping the older generation. So even if it were possible to do so, the cost reduction opportunity of moving high volume production onto a new technology node will dictate that move.
Having said the above, I'm certainly not arguing that HW3 can definitely hold its own - it depends on factors that are unknowable. I will say that the present shipment of apparently "HW4 Lite" configurations, with only a subset of the expected camera upgrades and still without high res radar, does not clearly indicate the obsolescence of HW3.
EDIT: reading again you are posting my response, I really don't disagree that what you say is overall possible. I myself have really hope for a more significant camera placement upgrade plus the new radar. What prompted my response here was really the quoted section where you have tried to use elon's own HW5 comment against him, and that I think was a step too far. I'm not an Elon sycophant, but I have a lot of sympathy for him when people rip him apart for saying what he believes.
We'll have to see what comes with the Highland and Juniper updates that might have a heavier HW4 update. In the meantime, it's highly premature to announce the uselessness of HW3 or HW4, based on the obvious point that something else will come beyond that.
