I don't know, this sounds a little bit like that sovereign citizen "wrong flag in the courtroom" stuff.
Even if they haven't replied, the original contract is still sitting there clearly stating that a certain set of assumptions are in place if you use the software. I don't see any way to argue that a non-reply implies consent to new terms or abandonment of any terms.
Even if they haven't replied, the original contract is still sitting there clearly stating that a certain set of assumptions are in place if you use the software. I don't see any way to argue that a non-reply implies consent to new terms or abandonment of any terms.