1. Price. Not viable, even using fantasy calculation of 2mil/flight (I suspect it will be at least 5-10 times more). You get 20000$ per ticket assuming full utilisation of 100 passengers. That's first class ticket price, or a seat at the shared business jet. So only rich people can afford it, but it is maybe realistic.
2. Utilisation - you will not find 100 people who simultaneously want to travel from A to B in the same exact hour while planning this trip weeks/months in advance. Planning trips is a vacation mode, business trips happen sporadically and quickly. This automatically throws off item #1 because then your price will skyrocket due to fewer people travelling.
3. Safety for passengers - no comments. Obvious blocker even on its own. Also Gov authorities will demand passengers training etc. (billionaire would go to months long training to save few hours of flight? lolno)
3b. Evacuation requirement. There is no possibility for quick evacuation of the 100 humans in spacesuits on the launchpad, so Gov will ban this idea.
4. G forces. Old and frail billionaires won't be able to fly this due to health concerns.
5. Landing pads. They need to be dozens of kilometers of both start and destination. This will eliminate any fantasies about saving time. And they will introduce immense additional expenses (so no 2mil flights).
6. Countries paranoia. Ballistic missiles of foreign force regularly overflying their countries in their airspace? Won't happen. The Axis of Pissed Contrarian Kids will block their airspace on principle (China, Ruzzia, all middle east, half of the South America etc.).
7. Reliability and reusability is not yet proven at all.
There are probably ten more issues with his plan if someone would sit and carefully analyze it and calculate costs.
tl;dr
Both hyperjets and passenger Starship is the same basic idea - futuristic travel via small but advanced "pods". Where "pods" is whatever futuristic looking vehicle of the day is used, with small capacity and unrealistic use case. Like hyperloop, autonomous cars, monorail cars, flying taxis, private rail vehicles etc. All complete bullshit.