No longer necessary to siphon data from users across the web using this beacon perhaps.

> data that they could use to target ads to you.

It didn't even have to be someone with an FB profile, they surely had shadow profiles of a lot of Internet users (when Zuck appeared before congress he dodged a question about this).

Just like Spotify or Netflix's recommendation engine, that's a gold mine for ads..

My guess? implicit behaviours are always more valuable than explicit behaviours, so when implicit engagement became the metric and measurable, Facebook didn't need people to deliberately engage with content to determine its value

Also..

* In that time we moved from desktop to mobile; clicking that tiny button was difficult on mobile and they couldn't replace it with a comparable mechanic

* Changes to third-party cookie and XHR rules in browsers made the data less reliable

These used to be on website - but websites themselves for the most part have stopped using them. I don't find every blog post with a "Click to like on Facebook" much more these days.

I did used to like reading HPE spec sheets for equipment and there was always a "Click to like on Facebook" button at the bottom. I'm not going to broadcast to my friends that I like eight different RAID card models thanks.