480 000 000 000 000 bits / 86400 sec = 5555.56 mbit/s
And you can send as many boxes as you like in parallel.
I fondly remember conversations on AmiNet - an Amiga - dedicated FTN network.
That was all done over PSTN with 9600 - 19200 bps modems. Latency was days. All this didn't preclude massive amounts of collaboration over it.
I'd rather question if lower latency delivers any benefit.
I imagine that in practice the postal service may start to decline your custom somewhere around the quintillion-box mark, or perhaps even before...
What if a billionaire launched a constellation of low earth satellites which provided Internet?
They're not, regardless of medium, the same cops and IP lawyers can get on it and track down people to arrest and sue according to whatever laws are on the books, good or bad.
What if this satellite Internet service is a multinational corporation, with the directly owning entities based in Russia and China? Or perhaps Sweden? Part of a conglomerate under the ultimate control of a corporation on Mars?
I think we'll definitely have crossed some threshold when we have our first extradition from a different gravity well.
Today, if people in Russia or China run the servers there isn't much the EU can do (see: scihub and the US, for a long time piratebay too). You don't need a massive indestructible satellite constellation for that.
I'd also add that a billionaire isn't the criteria you're looking for here even if it was a policy targeting the people running the wire. It's a foreign government with sufficient military power to deter the US from arresting you, and sufficient technological power to set up such a network. Maybe it's a Russian Billionaire who launches them in your hypothetical, but it's the Russian government who provides the security that allows him to do that.
I was imagining containerized server clusters in low earth orbit as well, with the ability to rapidly export the entire state of servers across super high bandwidth laser links. Everything would be done remotely, and the corporations running them would also be in Russia, China, Mars, etc.
(Containerized in the sense of hardware in a shipping container, not Docker, though that would play a role as well.)