> Worth mentioning that Wikipedia gets an order of magnitude more traffic than the Internet archive.

With an order of magnitude less data to host, though. The entirety of Wikipedia is less than 1PB [1], while the entirety of IA is 175+ PB [2].

Traffic is relatively cheap, especially for a very cache-friendly website like Wikipedia.

[1] https://en.wikipedia.org/wiki/Wikipedia:Size_of_Wikipedia

[2] https://archive.org/about/