Before speedrun.com was a thing, times were posted on a text document. I don't know the specifics, but I think video proof was not a thing back in the day. Or if it was, the video was deleted from Twitch/Youtube/wherever it was, and only the time was exported to srcom without the video because there used to be video proof, but it's been deleted and it can't be found anymore.
The rule used to be "top 10 or top 50% (whichever is smaller) needs a video" even here. But this was recently hanged due to a shift in community opinions on proof standards, which is fair.
Before speedrun.com everything was on a google doc, which had to be manually updated. As a result, a lot of runs were added after they were seen live before they were highlighted, and some of those runs never got highlighted because the runner intended to improve again soon, but that improvement never happened.