Because they thought it was too ‘woke’ and wanted to burn the books.
FWIW you can download it: https://en.wikipedia.org/wiki/Wikipedia:Database_download
Edit: Lots of good answers. When I ask the question I mean the main site. We would all have access to it. Hell I downloaded the text yesterday on two computers. I mean could the masses ever be denied access to wikipedia in the only form they are used to?
Unlikely. They have data centers in several locations all over the world, and there are countless backup copies downloaded onto personal devices everywhere.