can anyone think of like, a crowdsourced text adventure where the story itself had been built out of user-submitted content?
@suricrasia Technically (not really) the SCP wiki? There's also Cataclysm Dark Days Ahead (And I guess any other community-run open source text games) but that's a rogue-like and I don't know how much of the community can actually user-submit content.

I know these are not really text adventure games but they're what this post reminds me of.