It needs to come down. However tragic the fire and the deaths were, we all must gradually move on after tragedy strikes us, and keeping the ruins of this block looming over the neighbourhood, must make moving on with life very difficult. By moving on I do not mean forgetting, or mourning the less for those who have left.
If you have read Charles Dickens Great Expectations you will remember Miss Haversham who was jilted at the altar and spent the rest of her life wandering round her house alone, still wearing her wedding dress, with the bridal garlands still up and the wedding reception still laid out, mourning her loss and doing nothing else. What a wasted life. I think Grenfell Tower is a modern equivalent of the wedding breakfast. It needs to be demolished, the site turned into a garden and those that mourn can see the hope of flowers growing in an area blighted by death and destruction for so long.