I've been using Opera and Opera GX for years. I recently switched back to Opera from GX after an update changed the UI to New Look, which turns out to be buggy. I later discovered that you can turn New Look off but, as has happened before, Opera just presents you with an unexpected change and doesn't tell you how to revert it if you don't want it.
I'm offering my feedback because returning to original Opera after an absence has really clarified some of the concerns I've had about GX. I was originally attracted it to it as a gamer and because of it's customization features, but over the years I feel that it's suffered from serious feature creep, stuffing more and more unwanted, unnecessary features into it which just clutter it up for no good reason, while basic browser functions and elements remain relatively undeveloped and appear increasingly outdated.
Here's an example
Regular Opera, on the left, has a more compact layout with virtually every tile showing a recognizable logo. Opera GX has larger tiles, but they're just blank tiles with the URL on them. It looks messy and overcluttered, extremely outdated next to regular Opera So I really would have preferred that the GX devs had spent more time improving basic features and functions rather than just stuffing in more bloat like mods and shaders, etc.