when I was little and I'd play minecraft alone I absolutely would get that feeling, it felt so empty and isolated. minecraft feels like it takes place in a ruined post-apocalyptic world where you are the only survivor of your species, so it makes sense that feeling could creep in after a while. there are significantly more features in the game now to distract from that feeling, compared to when I was younger, and I've become quite desensitized to it so I rarely get that feeling anymore. but it still settles in sometimes when I come across a ruin or I have to sit and wait out the night to pass.