Lithium Related Media Articles, page-24315

Definitely correct.
Not all lithium is equal.
Not all brine is equal either.

It's correct that most brine operations and projects in Sth America are not very profitable, some might have to produce at loss if they were in production atm.

This is an old table below but it's still valid.
Atacama has very high lithium in brine but it also has very high magnesium which is hard to remove. However the very high potash ration in it offsets the cost of removing the magnesium. So it's very profitable.

You can see the Mg/Li K/Li and K/Mg lithium ratios at the last 3 rows. Atacama is the best.

Salar de Olaroz where Arcadium (ex Orecobre) has nearly 1/3 lithium of Atacama as you can see. Cauchari lake has less lithium than Olaroz btw. There are a few projects there as well.