Checking the response from the maintainer shows another different story: https://bugzilla.gnome.org/show_bug.cgi?id=679658#c12

>Implementing keyboard selection inside vte means that every terminal based on vte benefits; adding only hooks for you means that all the other terminals get no benefit.

The patch being pushed wasn't going to help other projects. The developer of that project was working on a fork of the library but it appears it didn't get much use and was abandoned: https://github.com/thestinger/vte-ng

I don't see much more that anyone from GNOME could have done there.

libadwaita exists solely to move Gnome specific stuff out of GTK into libadwaita.

And it's hard to see how an open source project with as many developers as Gnome/GTK have can have some secret agenda that is counter to what they are saying publicly and creating libraries and code publicly to implement.

> it's hard to see how an open source project with as many developers as Gnome/GTK have can have some secret agenda

How many serious Gnome/GTK developers are there who are not IBM employees?

That question is a non-sequitur. But to give you a type of answer, most of libadwaita came out of Purism.