I guess it depends upon what you are expecting? If the Sainsbury Wing had been a completely new building that was unconnected with the National Gallery, then having a radically different feel may well have been the right approach. As it happens, I tend to think that the final building is quite sophisticated; it is clearly an 80s structure (both inside and out) but it definitely also engages with the design of the main building in a more subtle way than the original proposal. And there are also questions about certain sites being considered “national heritage” - Trafalgar Square probably qualifies as one of those - although this should obviously not be an overriding factor.
Note: I am not saying that I disagree with you. I love new buildings, especially ones that do interesting things with the area they are in. Most of the ‘skyscrapers’ in the City provide an excellent juxtaposition with, say, St Paul’s cathedral (and I’ve sometimes noted that people in the 17th C probably complained about Wren’s monstrous carbuncle a lot too!) And had the original design of the Sainsbury Wing been constructed, I dare say I would have been fine with it. So yeah, I’m a hypocrite.
