Sorry, I used *= because that's what I remembered the old syntax to be. If it's += then that's what I should have used.
In any case none of those, other than just =, are supported any more. (And are deprecated even in Oracle, you know.)
The reason they don't work is that there is no way to handle the example that I showed: Where an outer join gets incorrectly converted to an inner join. That is, there is no way to distinguish between the conditions that create the join and the conditions outside of the join. Using the LEFT JOIN (or RIGHT JOIN, but that's just syntactic sugar...all RIGHT JOINs can easily be converted to LEFT JOINs) syntax, the ON keyword allows you to separate JOIN conditions from common WHERE conditions.
An optimist sees the glass as half full.
A pessimist sees the glass as half empty.
A realist drinks it no matter how much there is.