You’ll regularly find a link to a secondary source that contains a reference to a primary source. If you just want generically available historical, scientific, or broadly epistemological knowledge, its great. If you want an on-the-ground testimonial from an eye-witness, it may give you the start of a breadcrumb trail towards your destination.

That said, the bias endemic to Wikipedia is largely a product of its origins - primarily English, western media focused, heavily populated by editors from a handful of global north countries. If you want to learn about the history of a mayoralty in Saskatchewan going back to the 18th century, its a rich resource. If you want to find out the political valence of the major political parties of Nepal or Azerbaijan, you’ll find a much thinner resource.

Some of that is a consequence of the editors (or absence of them) around a particular topic. Some of that is a consequence of the moderators/admins graylisting or outright blacklisting sources. Newer sources - 404media, for instance - aren’t tracked while older sources that have changed management significantly and lost some of their trustworthiness - WSJ, CBS, National Geographic, as recent examples.