A few minor critiques are in the wikipedia article[1].
Most of the ones I remember were theme developers dropping support for their themes during minor gtk3 releases. I remember seeing a lot of articles about this, but I wouldn't be able to point you to them now.
Most of the ones I remember were theme developers dropping support for their themes during minor gtk3 releases. I remember seeing a lot of articles about this, but I wouldn't be able to point you to them now.
[1] https://en.wikipedia.org/wiki/GTK#Criticism