There were plenty of bugs. But there were at least a few releases that addressed these. Snow Leopard is probably the most notable which shipped with no new features. I think I first started on Panther and there was at least 1 upgrade during the PowerPC times that really cleaned things up and improved performance quite a bit.

Which is why I speculate that overall, it might not be better. You had to wait a couple years to get the fixes. Now they probably ship the fixes and new features on a more regular basis.