Very very interesting discussion. Few more questions:
- What if at one point in time we have zero nodes supporting SegWit? What happens to all the SegWit transactions completed before that point? If old-style nodes do not read beyond 1 MB, does this mean that all those SegWit transactions will be like they never existed?
I think that this is a highly theoretical question. Theres very close to zero probability that nodes would for some reason abandon SegWit.