So far I like the bundling of lsp and so on, it worked nicely out of the box to bring in my Rust projects ... it's nice to have it all set up.
But there's more... opinionated stuff in here that's frustrating. C-x u for undo is wonky, and C-g does not appear to be working to abort/get out of prompts. My fingers were tripping all over the place.
I feel like by the time I'd unpeeled enough of this guy's opinions and undone all the non-standard stuff in here, I'd be best to just start over.
For me, C-x u opens a buffer for undo-tree, not sure if that's what you meant or not.
It's possible I customized for C-g and or C-x u; I haven't changed much in .emacs.d/personal recently, except for adding a few scripts.
In any case, glad you gave it another shot, but perhaps it isn't your cup of tea. It's great that Emacs is (and has long been) able to adapted to a variety of needs and preferences.
And C-g, yeah, I don't know what it was doing. It got really weird.
In general this thing seems to want to open buffers all over the place. It's... visually confusing and I kept losing cursor focus in the task I was trying to focus on.
For what it's worth, I happened across bbatsov/prelude in 2011, not long after it started being developed, having no prior emacs experience. The notice you mentioned was one of several that nudged me to learn and use the various key combinations, so I'm grateful for the notices, but I understand that not everyone would be.