Risks of too much low interest data in wikipedia include:
* Not enough interest to update wiki when the subject changes; then wiki becomes out of date and unreliable.
* Too few eyeballs allows false information to be added (accidentally or intentionally)
* Becomes harder to do wiki-wide changes (of course it's inevitably too large for manual wiki-wide changes, but you can imagine more articles means more corner cases will be hit that will get automation mistakes or require more complex automation. Think info-boxes used in novel ways etc)
The first two are arguments against letting an individual write a single article about a unique topic, not against allowing a vibrant community of people with special interests document them in a public reference.
The third could be solved by only deleting pages that use the wiki language in unmaintainable ways.
* Not enough interest to update wiki when the subject changes; then wiki becomes out of date and unreliable.
* Too few eyeballs allows false information to be added (accidentally or intentionally)
* Becomes harder to do wiki-wide changes (of course it's inevitably too large for manual wiki-wide changes, but you can imagine more articles means more corner cases will be hit that will get automation mistakes or require more complex automation. Think info-boxes used in novel ways etc)