I didn't know Liddle had said anything about Nelson Mandela's death so I looked some up. I found, among other things, an article in the Guardian. I didn't see anything in it that doesn't bear repeating. He is reported as saying that he thought the BBC coverage was over the top. One can agree or disagree with that but it isn't awful. He is quoted as summing up the coverage as: "famous nice black man dies". One can think that dismissive or grumpy old soddish, or not. And he's also quoted as saying that he was sorry Mandela was dead.
People are always saying how sad it is when someone famous dies. I never find it sad. I find it inevitable. People die, especially when they get very old, as Mandela had. Saying this does not affect my interest in the man's story and his importance in the history of South Africa. If other people find the death of a famous person sad that's absolutely fine. What isn't fine is thinking everyone else must feel the same or they are a bad person.
I wasn't sad when Michael Bond's recent death was announced either. There was a gush of emotional overflow in the media over it and then everyone forgot about him again until they next read his Paddington stories. What I wondered is how many of those gushers had spent even a minute thinking about the creator of Paddington in the decade or two before he died.