Let's see:
Perimeter defensive rules changed to benefit offense
League expansion watered down teams, to this day the nba hasn't gotten back to the same level (someday I'm sure)
Add in poor officiating that seems to benefit certain teams. Obviously add in Jordan/Lebron calls.
I'd love to see a good team from the 80's (pick one) but let's say the Bucks play against current teams with current rules/refs. Moncrief, Lanier, pierce, bridgeman, sikma, Johnson, Buckner.
Granted that list is off the top of my head so not sure if all played together but they were as I remember below Boston and philly in playoffs. Brian Winter was a sharp shooter that also played. Cmon Sikma would be a beast in today's nba, an old bob Lanier same. As older fans we don't compare and don't think too much about it. As soon as "Jordan rules" started the nba simply is a weaker product.