macOS unable to open any non-Apple application

Even beyond unintentional glitches at Apple, just imagine what this could mean when traffic to this infra is disrupted intentionally (e.g. to any "unfavorable" country). That sounds like a really serious cyber attack vector to me. Equally dangerous if infra inside the USA gets compromised, if that is going to make Apple computers effectively inoperable. Not sure how Apple will shield itself from legal liability in such an event, if things are intentionally designed this way. I seriously doubt that a cleverly crafted TOS/EULA will do it, for the damage might easily go way beyond to just users in this case.

Again, maybe (and in fact: hopefully) I'm just getting this all wrong. If not, I might know a country or two where this could even warrant a full ban on the sale of Apple computers, if there is no local/national instance of this (apparently crucial) infrastructure operating in that country itself, merely on the argument of national security (and in this case a very valid one, for a change).

All in all, this appears to be a design fuck-up of monumental proportions. One that might very well deserve to have serious legal ramifications for Apple.

The answer is pretty simple: these problems are extremely rare, they don't last very long, and they tend to have fairly simple workarounds. You seem to have a principle that any non-zero chance of being affected by a problem of a certain type is a complete deal-breaker, but most people when buying a computer probably just subconsciously estimate the likelihood and impact of this type (and all other types) of problems and weigh that against other unrelated factors like price.