Famously the actual main library at Pasila has a much larger book collection. Oodi is more of a community space / show piece.

Fair, but it is part of a pretty large library system and you can order whatever you want to pickup at Oodi

Well, book collection of the particular library doesn't matter much nowadays since you can order a book online and it will be delivered to your closest library. So it's more like a public space.

Oodi was noted in the media to be particularly unimpressive when it came to actually having books back when it opened.

https://www.hs.fi/kulttuuri/art-2000005933560.html