I’ll not flog a dead horse too much re some of the other points below, but here’s my two cents. You say that the developer was clear that NMS is not a multiplayer game. I’ll agree, he did not promise all the big features one would expect. However, he did, as you point out, indicate that there would be interaction or at least encounters with other players.
Yes, he’s clear about the ‘ potentially — very rarely’ bit and how it’s not a focus, or that NMS is a solitary experience. But when given time, not under a rapid-fire barrage of questions, he volunteers an explanation how the player cannot see themselves, that the only way to know how one looks is for another player to see and tell them (0:13–0:20 in the linked compilation video).
Along with the other statements that you pointed out or linked to, he was pretty clear that at least the ability to meet other players in-game was a big part of the game.
If that was cut, given the volume of comments he made, he could have at least gone on record to say it may not be delivered after all. That’s basic courtesy.