So there was no reason to get rid of (i.e. devalue) it, neither for Brazilians nor external investors.
That was achieved via huge dollar reserves and tight money supply. The government had been accumulating USD to point they had ~4x as much of it in reserves than all reais in the economy (M1) when the real was launched.
Brazilians were used to price things in dollars, and saved dollars whenever they could for obvious reasons. They had been forced to adopt new currencies in the past which immediately lost value as you suggested. When they were forced to adopt this new currency which was provably as valuable as the dollar, people understood that it was safe to stop raising prices.
Of course the dollar reserves wouldn't last forever and a few years later that policy gave way to other measures, but it was a decent starting point.
A very good, very long view (in Portuguese): https://www.mises.org.br/article/1294/uma-breve-historia-do-...