Margin loans didn't exist back in the 80s so it wasn't an issue, they only started being offered to retail investors in the early 90s (I think Leveraged Equities were the first to offer them).It did not happen that way last time around in the 1980's,at the time there seemed to be a logic in such incompetence of the experts around that time
but ASX investment class stayed the same the only cab off the rank was investment property
I think this time around margin loans could also be restricted and negative gearing disallowed. An interesting approach could be to treat the two classes combined as investment income, so losses in one could still offset income in the other. ..but this could have loopholes.