That's a great example. The hypothetical Brazilian could vote for a politician that does not promote burning the rainforest [1], which contributes to the negative effects of climate change on the people of Sierra Leone [2]
[1] https://www.bbc.com/news/world-latin-america-49450925
[2] https://www.sl.undp.org/content/sierraleone/en/home/presscen...
This line of argument conveniently sidesteps the question of whether mainstream news is the best way to find out what is going on in the world or learn about electoral candidates.
It can be reasonably argued that allowing one's self to be influenced (or, manipulated) by mainstream news is likely more of a hindrance than a help in making good decisions or taking meaningful action to improve the world or support/elect good candidates.
By avoiding the day-to-day barrage, one is better able to focus their attention and energy on things that are important and impactful.
There are plenty of ways to learn about what is going on in the world and find out about electoral candidates, outside the corporate media circus.
Abstaining from frequent infotainment aka "news" does not equate to being ignorant of important things happening in the world, nor does it equate to abdicating responsibility for all the things you can practically influence.