Isn't a tl;dr meant to sum up the article?

What it actually says is that whilst the cost is an issue, the primary reason is that these companies don't want Google ads seeping into their products.

Data's only half the equation, building up a service with all of the features to what you need costs $. From the Switch to OSM site "Serving your own maps is a fairly intensive task. Depending on the size of the area you’re interested in serving and the traffic you expect the system requirements will vary. In general, requirements will range from 10-20GB of storage, 4GB of memory, and a modern dual-core processor for a city-sized region to 300GB+ of fast storage, 24GB of memory, and a quad-core processor for the entire planet."

Don't get me wrong OSM is a fantastic initiative. It will be very interesting to see if a slew of competitive services spring up in the map 'service' arena, using OSM data.

For a while, Google was far from transparent about potential costs and some interpretations were indicating that the cost would be enough to destroy certain services.

Whilst Google eventually opened up, despite the prices being reasonable, most affected services had already finished (or nearly finished) their conversion to OpenMaps.

Given the cost of finishing the conversion or sticking with GMaps for a reasonable fee, many took the decision to convert.

Google kinda dropped the ball here and got a lot more damage than they needed to.