Also, I think training camp was such a drag back in the day and players had a stronger aversion to getting back in shape, I recall hearing that vets would purposely wait until the last minute to sign with a team just so they could miss training camp.
Looking through old transactions on basketball-reference.com, you see a lot of rotation level vets signing in mid-to-late October or even early November.
Sherman Douglas signed with the Nets on 10/31/97
Malik Sealy signed with the Pistons on 10/25/97
Terry Cummings signed with the Bucks on 11/2/95
Tracy Murray signed with the Raptors on 11/1/95
Terry Porter signed with the Wolves on 10/14/95
Jerome Kersey signed with the Warriors on 10/18/95
Antoine Carr signed with the Jazz on 10/29/94
Avery Johnson signed with the Warriors on 10/25/93
These are all rotation guys playing 20+mpg, we're not talking fringe guys hoping to fill the final roster spot or aging vets with one foot in the grave.
And that's just guys who switched teams. It doesn't count all the guys who re-signed but purposely dragged out contract negotiations to miss camp.
In this day and age, could you picture quality players like J.J. Redick, Aron Baynes, Rajon Rondo, or Trevor Ariza still being unsigned at this point in the off season? It used to happen in the past because guys would wait to sign just to miss camp. If you know you're going to sign with a team, why sign in July/Aug/Sep when you can just sign in Oct/Nov? Same money, less work.
The players' off season conditioning and the training camps necessary to get them back in shape were just a completely different animal in the past. I think the league is in a much better place now.