I think you're underselling the tail end of those Pistons teams, the Wade/Shaq Heat combo, Caron's Washington group and even the last of the Kidd/VC/KMart Nets. From 2003 through 2007ish, the East brought some real talent to the table.
I think you are overvaluing the Wizards (peaked at 45 wins) and Nets (peaked at 49, averaged 44.75 from 2004-2007), post-2004. The Pistons of 2004-2008 were quite good, averaging 56.6 wins per year. The Shaq/Wade combo was dead by the time James's teams could really compete. In 2006, when the Heat won, the Cavs got to 50 wins. The next year, the Heat only had 44 wins. The next: 15. I don't think any of these teams were real threats aside from the Pistons. A tough team to beat, but hardly a gauntlet.
From 2008 onward, though, I'll grant that it's been a trainwreck. But I'd say the same thing of the East through most of the '90s, when it was really just the Bulls & Knicks with lesser challengers like the Pacers, Heat, Cavs and (if you want to be charitable) the end of the Bad Boys Pistons and Bird's Celtics.
The Knicks dominated their division for over half a decade with the most overrated superstar in league history and literally no one else of historical note. Jordan's in-conference heyday didn't come against the heavyweights.
A quick contrast. In James 5 NBA Finals appearances, these were the number of 60 and 50 win teams in the conference, including his own, and .500 or below playoff teams:
2007: 0 60-win, 2 50-win / 3 .500 or below
2011: 1 60-win, 4 50-win / 2 .500 or below
2012: 0 60-win, ~3 50-win (pro-rated) / 0 .500 or below
2013: 1 60-win, 2 50-win / 1 .500 or below
2014: 0 60-win, 2 50-win / 1 .500 or below
The Eastern Conference, in Jordan's 6 NBA Finals appearances:
1991: 1 60-win, 3 50-win / 2 .500 or below
1992: 1 60-win, 4 50-win / 3 .500 or below
1993: 1 60-win, 3 50-win / 1 .500 or below
1996: 2 60-win, 3 50-win / 0 .500 or below
1997: 2 60-win, 6 50-win / 0 .500 or below
1998: 1 60-win, 5 50-win / 0 .500 or below
I'd say that the East of Jordan is certain not
great, but far better the the East that LeBron has had to go through.