It's not as simple as only defining success by stats OR titles. Both are important. Individual and team success needs to factor into the discussion because we're comparing individuals, not teams.
Longley has more titles than Bogut and Simmons, but I don't think that automatically makes him the best all-time Aussie.
Longley won his titles playing with Jordan, Pippen and Rodman. Bogut won his title playing with Curry, Thompson, and Green. It's not as if we're talking about two players who were the best player on their respective championships teams. Not even close.
Both players fulfilled their role and contributed to the title, no doubt. Longley fit well in the triangle with his passing and Bogut gave the Warriors rim protection they needed.
But let's be real. The Bulls could have switched Longley with any number of other centres who could have fulfilled that role at a good enough standard for the team to still win a title. The same is true for Bogut. But you couldn't have found too many shooting guards to replace Jordan, or point guards to replace Curry, for the teams to still be as successful.
It's not as simple as using team success as the only way to compare players. If it was, Jud Buechler was better than Karl Malone and Bill Wennington was better than Patrick Ewing.