There's no argument over that. The argument is that if his stay at the Ecuadorian embassy was akin to prolonged "psychological torture", he could have surrender

There's no argument over that. The argument is that if his stay at the Ecuadorian embassy was akin to prolonged "psychological torture", he could have surrendered himself to British authorities and received the same treatment as any other prisoner. The strongest case you could make is that his life at the embassy was akin to living in prison.