Any advice on how to deal with this very long, but informative, discussion?
Some things could be folded into the answer, some split into separate questions?
Normally, you flag any comment of a chain for moderator's attention (don't forget filling the annotation field). A moderator would then move comments to a chat.
However, if you think that some comments can become an answer (probably, by adding some further details), you may simply comment like
@username, your comment is worth being converted to an answer or so.
Quite often, however, people leave comments because they think they don't have enough information to post an answer (and face downvotes for insufficient explanation). So you can also write your own answer based on others' comments. If your answer is substantially based on someone else's comment (e.g., you feel that your input is minimal), feel free to mark your answer as Community Wiki (CW).