That is only one facet of what a library does, and some of those other facets require other forms of functional architecture. A library can be a place to study

That is only one facet of what a library does, and some of those other facets require other forms of functional architecture. A library can be a place to study. Some building designs are more comfortable than others. That's why some libraries (like the Ningbo New library mentioned) have dedicated reading rooms. A library built only for finding obscure knowledge is not a good library for helping young children learn to enjoy reading or research. Knowledge isn't only written, nor only acquired by reading. The Oslo library mentioned, for example, has recording studios, rehearsal rooms, and game rooms. Lectures and other presentations may be better done in an auditorium than in a room tightly packed with bookshelves. Libraries can also have exhibition space, including for local art and history. Perhaps only a few hundred people have ever seen the works of a local artist - surely that makes it "obscure knowledge". Exhibition space requires different architecture than book collections.