anyone else find optimizing a youtube stream for seo harder than the guides suggest?

Yeah, because most guides are written for uploaded videos. What helped with streams: schedule it in advance so the watch page exists for a day or two with the title, description and thumbnail already set. Afterwards, go back and edit - rewrite the title for search instead of for live viewers, add chapters, trim the dead air at the start. The replay is what gets found later, not the live event.