Many Westerners consume as much as 2g/kg of protein daily. More than enough. The potential dangers of excessive protein consumption as well known. That is why many people who low carb replace the lost carb calories with calories from fat rather than protein.
From one of their websites, it appears that Australian dietitians think it is OK to consume 1.25g/kg of BCAAs. On top of the usual protein intake.
Are they completely ignorant of how the nitrogen in BCAAs is eliminated from the body?
Do they really think that the reference quoted had sufficient sample size or follow-up time to exclude an increased incidence of renal failure in users of that dose?
Their reference to a dose of 1.25g/kg also ignores the fact that many of the gym crowd who may consider taking this have a weight which exceeds ideal body weight, but no, they they didn't give a recommendation in grams per kilo of ideal body weight.
Addit: People who take BCAAs may also be taking creatine. Add this to your nitrogen load.