I don't think teams have fully calibrated the risk of the play in tournament and the potential reward of the lotto odds changing. Only the top 6 teams in each conference being in the playoffs leaves like a 25%-33% chance that a team that should have made the playoffs ends up in the lotto. Happened to Clips last year... Warriors the year before. Its only like a 2.5%-9% chance it jumps to top 4... but it will happen at some point.
While they may not tank... they might shut it down like the Lakers did last year. They end up with some injuries and nothing to play for so they land 7/8 which gives you a 25-30% chance.
It is more likely those picks fall between 18-30 than we get a top 4 pick though. Teams that aren't confident that they will be good don't give up far out unprotected picks though... so you just have to bet that bad **** will happen.