https://kbclip.com/ is something we've been using as you don't have to deal with the slog of searching through all the inane conversations to find what you're looking for (and it's a lot more structured). That being said, you do have recognize that you want to save something up front.
Maybe use both?
I'm happy to answer any questions people have. Initial feedback has been pretty positive so far.
Valid point about how KB Clip is "opt-in". that's intentional as many channels can be like a firehose. The core tenet of KB Clip design is that the most important info should be clipped and it should only take seconds to do so. I love a good pun or gif war and anyone, but not in my wiki or KB.
That being said, I've also got some roadmap features that help surface conversations that heuristically might be important to save as well.
Works more like a searchable knowledge graph, with the ability to identify users as nodes. Ie you can search for answers in the messages, links that probably have answers and people who would likely know the answers (we then link to said people).