It happened a few times in the early 80s. Worst was in the 83-84 season when it was so bad and obvious that they changed the system after that year. The Bulls, Rockets, and I think Pacers and Clippers tanked so clearly the league was embarrassed. They all wanted Hakeem and back then the worst record in each conference got into a coin flip for #1 pick.
Similar things happened with Ralph Sampson years before.
But in 84 the Bulls traded the one time franchise player and lost like 16 of 17 as the other best tanking team lost about 15 in a row.
NBA wouldnt let it happen again. Thats why we have a lottery now.