Good content was always a marketing strategy. For a while DO's content ranked high for a lot of tech searches. Rightfully so too, it is high quality.

Then another Google algo change pushed high quality content, like DO's tutorials, down in ranking. No need to spend money on something that isn't having the intended effect.

I worded this a bit tongue in cheek but seriously, search results have gotten really terrible in the past few years. At least DO's stuff was helpful. Now the first page is full of spun garbage just because it follows the new outline format that Google loves.