I worked at Nokia in the maps unit around the time that MS tried to leverage OSM and ended up licensing maps from Navteq. Trust me, everybody was very interested in OSM but also very aware of the legalities of that.
Google started building its own maps in response to Nokia first buying Navteq (in 2006, which Google was depending on at the time) and subsequently offering free navigation on the N95 (S60) and later phones.
Right then the obvious move for Google would have been take open street maps (it was already growing quite nicely then) and improve on it. They even created their own community map tool so they obviously liked the idea of crowdsourcing their data. The reason neither Google, MS, and later Apple opted to use OSM is very simple: the OSM license is a problem for their level of ambition. The baseline OSM experience is nice but the differentiation is what you do on top. That would be things like street-view, having lots of POI data, traffic information, public transport maps, 3D buildings, etc. Those are differentiators in the market and key for these companies to attract more users. They're not interested in helping their competitors get their hands on that. Apple at some point fell out with Google and it became crucial for them to take ownership of the map experience: so they ignored OSM and built their own maps. That's expensive and they pulled it off successfully and it's a decent; competitive experience these days. But it was a conscious choice and not some strategic blunder.
The dilemma these companies have is wanting to keep those things proprietary and OSM not really allowing for bundling proprietary and open data. So, you have basically Google and Apple bootstrapping their own maps in the last 10 years and Navteq and Teleatlas surviving as key data suppliers in the hands of Here and Tom Tom.
Each of those spend billions on improving their maps every year; they are competing with each other and with the OSM community; which is impressively good these days as a baseline map experience. The point this article is making is that a lot of companies that are smarter about pooling their resources are rallying around OSM thus making it increasingly competitive with these big proprietary data silos. So even poring billions in Google and Apple Maps may long term be not enough to keep up. OSM makes maps a commodity and bad maps a liability. Making good maps is expensive and unless you have a trillion $ valuation, you probably should use OSM instead of embarking on your own maps project at great expense. Apple and Google are doing well. I'd argue Here maps is a lot less attractive these days then it was when Nokia bought Navteq (which became Here later). It's still alright for car navigation but that's just one niche application of maps these days.