I use Movist Pro (Mac-only) for videos that work with youtube-dl. Once you set it up it's like magic. I can set keys for any speed or jump size I desire.
I have gotten pretty good at watching fast and jumping around to see if this vid is worth a look, or will cover the information I need. When I'm away from my computer and have to wade through vids on another machine it's like torture.
By the way, the modern internet is way better than the 1995- 2005 version. Everything you could want is there, you just have to learn how to get past the fluff and BS. I have fond memories of 1997 internet because for the first time I could access so much information from home, but I would never go back.
Might make a good browser plugin. Binary search, but for video. Tweaking the exact ratios might be an interesting problem. I'm thinking (no evidence!) that 30% for a forward jump and 15% for a backward jump might work better. Large jumps forward until you hit something interesting, then small jumps back to find the start.
The funniest part of that meme is that YouTube implemented a (now obviously removed) "wadsworth" query parameter that skipped the first 30% of a video.