The tax is that a businesses have to raise their prices in order to afford Google's ads, which are only able to be priced so high due to illegal business practices. That means you, the consumer, are paying synthetically higher prices for everything because of Google's ad monopoly. Paying the Google tax.
Not to mention that because Google is the de facto owner of Internet search, it essentially pits businesses against each other, forcing them to engage in a bidding war for limited space at the top of search results.
This, unsurprisingly, leads to higher and higher expenditures on ads, rather than on improving the product of a business. In the end, consumers end up with mediocre products with above average prices - advertising costs being passed on to end consumers.
These costs can be quite significant (I work in e-commerce space), ranging from 10% to 20% of the end price the consumer sees.
