Both Tesla and BYD had negotiations to buy Sigma Lithium, the largest lithium mining company in Latam, where the world largest lithium reserves are..

Bolsonaro, and the right in general, is known to be anti-china and could help blocking BYD acquisition, that would favor Tesla that would be able to buy it cheaper then if he has to outbid BYD...

Cutting the Chinese access to latam lithium would also harm their expansion plans and slow their grow.. That would also favor Tesla as the Chinese is owning the market in many developing contries and are growing fast even in Europe..

Even in the US the Chinese EV are a problem to Tesla, to the point the government quadrupled the import taxes on Chinese EV..