native nodes are no longer full nodes..
Is this not the problem (potentially) with both BU and SFSW solutions?
the funny part of SFSW is by allowing native nodes to continue.. not only will malicious sigop spammers continue to make sigop spam with native keys. but it opens up new attacks too.
basically meaning segwit doesnt 100% fix the issues
basically meaning segwit doesnt disarm everyone
basically meaning segwit doesnt get all the benefits it promised
and it opens new issues.
Which is probably why 95% sustained segwit activation signaling is needed. It's uglier and more dangerous than a coordinated hard fork.