I really don’t think that’s any worse than Edwards. I dare say that Edwards would say the same thing in fact. Except he would also add in the image of God hanging sinners over the fires of hell like a person holds a spider over flames (who does that anyway?!) and only holding them just above the fire out of his own ‘sovereign pleasure’. It might not technically be sadistic but the way Edwards frames it in his famous sermon comes relatively close to appearing that way.
The whole “people in hell want to be there” is frankly the most bizarre defence of hell I’ve ever seen. It’s never really seen in the Bible when describing judgement and when people say it, what they really mean is that those in hell would rather serve only themselves than serve God. If hell in a certain sense is giving people over to their destructive self-centredness, then that would be a more precise way of putting it. But they don’t want to be in hell per se. Its like if I have a really bad stomach ache and I haven’t eaten enough, then the best thing for me would be to go to the kitchen and get something to eat. I might not feel like I want to eat anything because I feel sick so instead I just lay in my bed scrunching up, trying to take away the pain and discomfort. In that situation, I would rather do that than attempt at eating something (even though eating something would be better for me). So I just lay there in my pain. But I don’t actually want the pain to be there.
People in hell (in whatever form, purpose, length, intent etc) don’t really want to be there. I don’t think it’s that controversial either to say that it’s pretty damn intense. ‘Weeping and gnashing of teeth’ is a pretty strong and vivid image, not to be taken lightly. So I don’t necessarily take as much of an issue with what Sproul says as you do. I take issue with the heart behind it, the intent, the purpose, the length etc (as you also do)