When there isn't a matching process for the long-tail, the pull is towards commodity.

If the niche buyer and the niche seller can't find each other efficiently, then they both tend towards the average.

They search towards the average until they find someone to transact with.

This makes sense, if they went the other way they'd be less like to find someone.

A marketplace that allows long tail consumers and producers to find each other could allow a market of bespoke craftspeople.

Without it, everything is constantly turned into commodities, into lowest-common-denominator.