Back then, they expected you to have 3 great players to win (or 9 really good ones if you went the Pistons route). Now, you're lucky to have two. And can win it with one. When the Celtics put together those 3, though hardly up to the greatness of yesteryear, they're a good deal ahead of the rest of the League.
Earlier in the thread it was said that Gasol wasn't a HoF. So you're basically have a defending and maybe 2 time champ with one great player. The 80's greats of the Lakers, Sixers, Celtics, Pistons and Bulls would be running off a ridiculous amount of championships in a row if they were around now. They just had to get through each other then, and won less (other than the Bulls, who came in at the tail end as all those teams were declining and dead, and had the League to themselves...one much worse than the League now, even).