Yeah I don’t like the glass effect and I realised it’s because it creates movement and drags your attention to things that should be background items. On the phone, video controls and app folders are particularly egregious.
I'm assuming since the Steam Deck push it's all changed. Either way, I don't tend to play AAA, but I've been able to play all the games I've wanted to without issue in Steam.
I seem to remember one of the points was the way GNOMEs plugin system was implemented plugins have no isolation so one bad plugin can cause all sorts of problems.
They were also limited in things they wanted to do with the default window tiling ui.