Sure, if you give them access to a better encyclopedia, that's not a terrible idea, I just think it's silly to have an absolute ban- "read at least two different encyclopedias" instead, maybe? "Cite N secondary sources you didn't find on Wikipedia"? And then they can find out for themselves how good or bad quality wikipedia is.

The thrust of the link here is that they aren't giving them alternatives, and just telling students to throw themselves into Google and hope they find something. Which, yes, isn't a bad skill to learn either- there's stuff to find out there- but it's setting them up for failure.