Who would've thought cryptocurrency guys would inflate whatever valid claims they might have had?
> After more recent changes to how Monero chooses its mixins, that trick now can spot the real coin just 45 percent of the time—but still narrows down the real coin to about two possibilities, far fewer than most Monero users would like.
Note that this is still a break, because quick Googling says that there are usually 4 mixins, so random chance would be 20 %.
Even more recent changes have made this better too. The research in the paper only goes up to Apr. 2017 or so. Since then, the "recent zone" has been a) reduced from 5 days to 3 days, and b) more recent zone mixins are included. We haven't quantified what improvement that makes, but it should help.
> After more recent changes to how Monero chooses its mixins, that trick now can spot the real coin just 45 percent of the time—but still narrows down the real coin to about two possibilities, far fewer than most Monero users would like.
Note that this is still a break, because quick Googling says that there are usually 4 mixins, so random chance would be 20 %.