It was Wordpress that offered the 100 year thing, but I think that was more publicity stunt than practical service - it was cheaper than their offerings for companies, so clearly aimed at individuals, but few people would care about their "personal brand" blog for so long after their death, and those that would probably have an estate big enough that they have a company running it while they're alive.
But in any case, AFAIK the maximum registration period for ICANN domains is 10-years into the future.
I keep my personal domain re-registered at least 5 years into the future, specifically so that if I was incapacitated for a year, or randomly decided to go travelling for half a year, or whatever, I won't miss the expiry date. I've had this domain for over 20 years already, so I don't mind 5 years extra, because I know I'm keeping it. Basically, everything the article said.
The domains for my company are all registered for 3 years up-front, and I try to renew them annually to keep at least 2 years before expiry, but I also know that if I died, someone else would either take over or wind up the company, and in either case they can deal with the domains as part of that, and if they have a long grace period, that's fine.
And in terms of the privacy concerns of the article, I have several separate domains that I use when dealing with companies. For a long time, I used addresses based on my main domain name with the company name before the @, but I'd already blocked a load of addresses where the company sold their client list (even some quite random companies like recruitment agencies seem to get tempted by this) and decided to just move to a couple of domains solely for this purpose. They have no obvious relationship to my name, so they're perfect if the e-mail address was later sold on.
To be honest, the biggest issue with dying isn't the registration of my domain names, it's that nobody else would even know HOW to get my e-mail from my private server. Currently, that's less of a problem than it might be as I use gmail as a client, so it fetches using POP from the various accounts on my servers, but if I died and nobody could access my gmail, it'd be a bit harder.
That said, in the UK after you die, the executor of your will has legal authority to contact any company you had dealings with before and take over your account or affairs. So honestly, as long as I document my bank account numbers, and make my property deeds and will easily discoverable, I'm not really too bothered about anything else.