King Robert’s actual son Gendry is everything that his alleged son and heir Joffrey Baratheon was not - beyond simply his physical appearance, but also his character and temperament. Joffrey’s one real claim to importance was that he was Robert’s son - which was itself a lie. Unlike Joffrey, who thought the throne was his by right but was utterly unsuited to rule, Gendry has many qualities which would make a fine king, but doesn’t even know he has a potential claim to it.
Honestly, I am so upset that Lady Olenna is gone, but so overjoyed that her last words were confessing that she murdered Joffrey. In her final moments, she got to witness that defeated look upon Jaime’s face, and know that the same look would cross Cersei’s. She gets to die knowing that while Cersei killed her family, she killed her precious first born son. She was such a badass woman, and even in her very last moments, she got to have one final triumph.