In 2015, Polish Wikipedia removed a significant number of users from the possibility of page editing without logging in (to be exact: more than half a million IP addresses were blocked – source).

Meanwhile, the definition of public good says that:
– consumption is non-rival,
– it is not possible to exclude anyone from the consumption of a given public good.

Despite the above-mentioned contradiction, Wikipedia and other websites (such as free content providers, e-services) can be considered public goods. The explanation of this paradox, as well as the connection of types of goods with business models of online businesses, can be found in the following article:

• Tymoteusz Doligalski, Business Models of Internet Companies and Types of Goods Offered, Journal of Business Models (2018), Vol. 6, No. 2, pp. 32-36
• Download: Internet business models (2018, pdf).