But in order to reply to someone directly, I think nested comments are a must.
I'm assuming you mean reply directly to someone else within a block of nested quotes, as the ideal way of replying to someone directly is to quote only them
The problem/trend on Geekhack is when someone for example posts a photo, and the next poster quotes them, continuing for several posts until the nested quotes snowball into a page of visual noise, when only the poster's reply is important while scanning the page.
It's a bit like quoting a long wall of text only to say a single word or sentence, it gets tiring in some threads.
It's a lot easier for the flow of conversation.
I'll respectfully disagree
And scrolling isn't the answer, but I'm at least content now with the userstyle though.