Highly doubt domain names will be required 50 years from now.
I’ve always said I want to make money on domains, I don’t want domains to make money on me.
What I mean by that is some point in the future domains will become redundant, they still have many years left in them yet, but domains have been around for 30+ years, do they have another 30 years in them? How people connect to the internet is going to change, no doubt about that, it's changed a lot in the last 10 years with smartphones and apps and there will come a time when domain names will go the same way as VHS and cassette tapes.
What people have to see is ‘when’ to cash out and not everyone will, many people will go down with the ship, still holding all these once premium single word domain assets which will go from being worth millions to worthless.
I always think people should always look to the future, when you make a sale, don’t put ALL money you made back into domains, reinvest a bit but always put money away, be one of those who can look back and say “I made money from domains” not “I lost money on domains”.