It's entirely possible that, through some strange quirks of circumstance, I've managed to avoid every problem space that would make me wish for generics.
In spite of that, it's unlikely that I've written implementations where using interface{} would be easier to read and reason about than not using interface{}. And the experience of the author whose blog post we're commenting on tracks with mine: "In my 5+ years working in Go, I can probably count on one hand the number of times that I felt like I really needed generics." I can too, just without using any fingers :-)