What you argue here (as I understand it) is that miners won't be able to 'understand' the SW patch, so they won't run it. I highly doubt both an assertion and a conclusion. I am sure it will be rolled over quite fast. But I have no real proof so we have to wait.
To migrate to a large change in infrastructure, you need to not only understand the solution, but also fully aware of the impact to the existing system and all the other systems that are dependent on them, potential security risk, evaluate its risk/reward ratio, and finally and most important, you should always be able to roll back to the old version if something went wrong
A soft fork qualify the last criteria, but still, from risk/reward point of view, I don't feel it worth the effort given the risk it involves. You change to a new untested architecture, what if after 1 years when majority of the nodes were upgraded to SW and found out that there is a deadly security hole that can not be covered, thus hackers can spend anyone's coin?
Bitcoin's value relies purely on its security model. Existing architecture worth a lot because it is robust and time tested for almost 7 years. It worth a little in the beginning, since there are too many possible security risk to break it apart, thus it must survive the test of time to gain its value. Now if you change to another untested architecture, it will basically reset its value to zero, and take equal long time to establish people's trust