At the Sydney Games, after almost every break in the fighting, one or
both of the Judoka were told to tuck in their joi before action could
continue. Often, this took a fair bit of time as the judoka had to
undo their obi and tuck it in before tying it up again.

Yet, watching the judo this time around, I have yet to see a single
judoka told to tuck it in (except after the match is over). Often,
they are fighting most of the match with the entire joi hanging loose.

What gives? Is it a change in rules or simply a matter of preference
by the official?