They, being smarter people than us, probably have a vague idea of the amount of data they are going to have to shift and store one thousands of people are playing this at once and uploading discoveries. But they have no idea how popular this will end up being. It could be anywhere from a flash-in-the-pan decent indy title to a minecraft-like phenomena. And as with every other game that comes out, you don't run out and buy massive amounts of cloud/networking until you have to. Also that's not including the crazy ways people might come up with the to break things or really put a stress on the networking. As with every game in existance, it will be played in ways the developers don't anticipate.
This type of game world is completely and utterly unprecedented. The fact that it works this well and doesn't fall over is mind-blowing. I would image at times they will have some networking issues just keeping it running at all, even at a basic level, and that's fine/normal. That happens with every networked game that isn't directly replacing a simimar predecessor thesedays. Imagine if everyone playing minecraft right now was automaically naming everything and uploading every patch of land they wakled on to a central minecraft server - the mojang devops would be sweating bullets.
They probably have a system for detecting if players are in the same starsystem and then transmitting micro detailed XYZ coordinates between players in the starsystem if close enough. But that's a reasonable step up in traffic in the games networked universe if enough people try to use it. It's probably only on when networking load is already low enough, and prioritises friends, it might not be enabled until a bit after launch, or it's just buggy, or only works for 2 or 3 players maximum, or it's just not fully implemented yet and they are seeing how networking goes with the main meat of the game first. In my mind it's peer to peer, and the server is used for negotiating suitable peer to peer connections when appropriate.
Of course it's not going to work every time. This is probably most analogous to Destiny - you can see your friends, and a few other people who happen to be in the same place, and there will be probems, I had problems with this at Destiny launch, and that game is comparitively straightforward and big budget, it's not having to consider location matches in a comparitively infinite universe!
But small issues like this doesn't mean we should be talking about courtcases, or lies, conspiracies or misinformation - madness! The game isn't even out yet (or barely just is). Lets also be clear here, this small aspect of the game is an aside. This isn't Eve Online. This isn't an MMO. We aren't paying monthy fee for a connected massively multiplayer universe. I have a feeling people are going to try to meet up in the dozens... or even hundreds, as soon as they even get a sniff of 2 people meeting up in a single location working, and I can see the same kind of comments rearing their ugly head when that doesn't work - of course it won't work!