The SCD doesn't eliminate all carbohydrates. It restricts certain types of carbohydrates.
For me personally, it was a good place to start experimenting with diet. And diet can be an excellent tool to help control and manage IBD. For those that find the SCD too restrictive, the book Listen to Your Gut offers different levels of restrictions, based on symptoms (as you heal, the recommended diet gets less and less restrictive). The book The New Eating Right for a Bad Gut is another excellent source of information on what foods are generally well tolerated and what foods are often problematic. Keeping a food journal to track your symptoms as you experiment is very helpful.
That said, most doctors and official organizations like the CCFA aren't going to recommend or even tell patients about dietary approaches because diet can't be tested with controlled trials - and it doesn't make anyone any money. I'd also add that dietary changes are just one weapon in the battle against UC. Most folks need to look at ridding themselves of harmful bacteria/flora and rebuild good flora, take healing supplements, learn to manage stress, etc. In my experience, all of these things need to work together and it's a long process - but well worth it.