Basically Google started monetizing it's semantic matching engine. It's what made Google results so great. For example if you searched the word "tall" it would include results for "big", "height", etc... with each word being ranked by closeness to what you searched.
Well now they made it so they will match monetisable words preferentially, like brand names for example.
It's likely the main reason Google results have been getting so shitty lately, the semantic match engine is one of the things that made the results great. Now it's an ad delivery engine and the results are crap.