I hadn't remembered them, so I checked your source... they were text counters with the labels "LOL", "OMG", "EPIC", "CUTE", "WTF", and "FAIL", apparently. If that was the actual implementation, then I can see several things that are different. The YouTube reaction button effort seems, in retrospect, to have made several horrible mistakes. The one that strikes me as a dead-in-the-water kind of mistake was mediating culturally between the commentator and the comment in what was probably a misguided attempt to be appealing.

+1 Interesting! (Slashdot has had an even more nuanced reaction system since the 1990s.)

What's different now is the visual representation - reactions as emoji.

And speaking from experience (the TapestryMaker social network platform has had emoji-based reactions for a couple years) it really does change the quality of the discussion. Especially on phones, one-click responses are a lot easier; so giving people a big one-click vocabulary makes conversation much richer. And having it representable visually rather than textually changes the image/text balance which for many people really improves their overall experience -- even though people who prefer text may not see it that way.

The difference? YouTube didn't loose anything. Facebook looses it's iconic brand: the white on blue 'like', that is just positive and teints the whole FB brand positively.

Oh, and people would use those things 'correctly', it's just too embarrassing sometimes. A simple 'like' is much more diplomatic.

I think you can still just click 'Like' the same way if you don't care about reacting otherwise?

Perhaps the average user is more tech and social-tech savvy now than then. That would be my guess. It feels like there are a lot of things now that seem intuitive that would've been a bridge too far for the average user to figure out 6 years ago.

"My aunt died" - like.

This was pretty much the case Zuckerberg presented for redesigning the button.

Snapchat