Taylor will never be Tony Carroll, neither will Milford, but inserted in a structure and with some training, their talent more than makes up for their defensive flaws. You keep hammering about Taylor's defense, but conveniently forget about the rest of his game.
Most halves are weak defenders, that is a given, especially when they get isolated by the opposition. Of course they need to train that aspect as much as possible, but it is as much the responsibility of the coaching staff and the players around them to mitigate that problem.
Yesterday, you could say that Taylor was mostly responsible for letting 2 tries in, but it was smart play by the opposition (in the same way Milford was mostly responsible for 3 tries we leaked against the Cowboys). But Ash was also mostly responsible for 5 tries in our favour and kicked 3 goals, yet none of that makes your post...
Our best player ever was also one of, if not the worst ever defender (in the line) at the Broncos.
In contrast, our worst halfbacks ever, were very good defenders!