Yep it's a mess. Most newspapers and official channels just avoid the word billion altogether, just writing "mil milhões" (a thousand million).
AFAIK the exception is the finance world, where I believe B stands for the short scale for a long time, and $1B has been used in newspapers for a long time too due to globalisation of the economy.
Isn’t “mil milhões” the proper term in the long scale? “Bilião” would be equivalent to the short-scale trillion, e.g., “NVidia vale $4 biliões”, which is equivalent to “NVidia is worth $4 trillion”.
AFAIK the exception is the finance world, where I believe B stands for the short scale for a long time, and $1B has been used in newspapers for a long time too due to globalisation of the economy.