Right now, his is ubiquitous because everyone has the same word. There's an odd network effect, where posting it on Twitter means something because everyone had the same exact puzzle. Nobody wants to see how you did on 6Word or whatever. It's a fun game, but it's not inherently fun (something like Scrabble already uses the same parts of your brain)... the fun comes from everyone having the same word every day.
He may not monetize it by selling it on the app store (honestly, who would buy? I think most people would just fizzle out rather than pay $1), but he'll definitely end up monetizing it in a unique way... the gigantic success of this will set him up for a huge number of opportunities (awesome job offers! promotions! raising money for a company! higher consulting rate!) that will last long after Wordle does.
He may not monetize it by selling it on the app store (honestly, who would buy? I think most people would just fizzle out rather than pay $1), but he'll definitely end up monetizing it in a unique way... the gigantic success of this will set him up for a huge number of opportunities (awesome job offers! promotions! raising money for a company! higher consulting rate!) that will last long after Wordle does.