The US and Brazil have eaten a lot of beef for a significant amount of time, so that had already been priced into the market.

A sudden spike in price requires a change in the market - e.g., the Chinese suddenly starting to eat more beef, wildfires wiping out grazing land, fuel price spikes making it more expensive to ship the product around, screwworm outbreaks reducing cattle headcount, crackdown on migrant workers reducing available labor for meatpacking plants, etc.