"Blockchain’s Killer App", what a sensationalist title...
Brave, and its crypto reward system could pose a threat to traditional web browsers like Chrome.
Hmm, not really. Unlike Chrome, Brave doesn't come as the default browser in most dektops/laptops meaning that Chrome still has a big advantage in terms of exposure to new public. Also, according to the website 'gs.statcounter.com', Chrome is the most used web browser in the world
[1] with a 62% market share, with the closest competitor being Safari with just 15%. So, according to those numbers, I'd say Brave could be competing with Opera and maybe Firefox.
Also, the article in the OP mentions BAT, but let's be honest, the majority of those 20 million users probably don't even care about BAT, they most likely fell for that single yet powerful word that grabs your attention and makes you want to try and download this browser...that word is "AdBlocker".
1.
http://gs.statcounter.com/browser-market-share