because, well.
from the Zettelkasten website:
Luhmann’s Zettelkasten is a collection of notes on paper slips with a special twist: It is a hypertext that he could navigate the drawer cabinet containing all the paper slips with a reasonable amount of time and energy. “Reasonable” means that it was reasonable for Luhmann, who, obsessed with his theory of society, was a workaholic and an enthusiastic bureaucrat. A hypertext needs to be surfable. On Wikipedia, you just need to click a link to get to the next article within Wikipedia’s hypertext. It requires more effort to follow a link if the hypertext is paper-based. The other problem is that you need a starting point for your ride. So Luhmann created his Zettelkasten to make his note collection surfable. He needed entry points and a mechanism to surf from one note to another in a productive way.
but that's beside the point. The description here is broadly applicable.
surfing leads to connecting things you wouldn't otherwise connect, the accidental/automatic discovery of context before content. lurking and community develop as people strolling past generates the web equivalent of "foot traffic".
Which is precisely what the corps have been tearing off limb by limb. Not just online, but also in the last 40 years of sub/urban planning.
But socially, not commercially. Relatedly, like diving into a wiki, especially the other wiki.
