There is a super accurate statement in that article:
We made a game that nobody wanted to buy
Everything else is trying to convince the reader that the above wasn't a failure on their part. There is an ever growing saturation of games (and music and books and indeed all consumable entertainment) - and success is down to a combination of making something that people want to play and making sure that those people know about it. One of the two things alone is insufficient tbh.
They did then go on to get nearly 2000 "very positive" reviews, which is indicative of many more sales. I think they did well in a sale later down the line.
Slightly directed at a sibling comment, but yes indie games (can) make a significant amount of revenue through non-release sales, even at heavy discounts. For example, Dustforce more than doubled its cumulative revenue through a 50% steam sale and inclusion in a Humble Bundle: http://hitboxteam.com/dustforce-sales-figures
I'm pretty sure the way this works nowadays if that your launch bombs you throw your game into as many bundles/deals as possible so I'm guessing those sales are at 5-10% of the original MSRP at best.
We made a game that nobody wanted to buy
Everything else is trying to convince the reader that the above wasn't a failure on their part. There is an ever growing saturation of games (and music and books and indeed all consumable entertainment) - and success is down to a combination of making something that people want to play and making sure that those people know about it. One of the two things alone is insufficient tbh.