Rubbish. If you want to put it down to 1 thing, it's more a fact of whether he is a bad buy rather than a bad player.
And for that there are a variety of factors that come into consideration including how much he would cost, his age, how many games he will likely play, other options (as you have pointed out) Whether he is actually needed.
FFS if we buy him, he wins us the next 2 premierships are you going to get more joy out of being right and proving the people who disagreed with you wrong, or the fact we have actually won 2 premierships?