Gets rougher and rarer to find such people the higher you go. But there are people out there. This will happen in every online game, so you cannot think its just a specific game. It's a human nature issue.
The good news is when you do find that person who reciprocates well socially, a great experience will make up for all the past flat lines. I'm the type of high level player who never forgets what its like to start new and to remember patience to reach mastery. Very rare however, for while I educate myself on min/max and JP PSO2 history, I still play my personal style and enjoy the journey of playing the game, not rushing to the end destination.
If you get a kudos/ saying "Nice character!" give a thanks in return. You can try doing that to start conversations but do not take it personal if no responses happen. People will have all kinds of reasons for being indifferent, and its best to just move on until you get a natural reciprocated interaction. For example, some people may not even speak English at all.
To those on Ship 3 who may be seeking a friend over chasing just digital goods or pride attention merits, I am more than happy to patiently welcome a new player friend who wants to go far in enjoying PSO2 in a variety of ways. I don't post much on forums, but when I see posts like this, I know there are others out there and so this is my effort to make a reach out attempt. When you put the ball in another's court, you simply wait if it gets passed back. Otherwise, just grab another ball and shoot somewhere else!
I mean really, think Dudu-like odds when it comes to this. You'd feel good getting that perfect augment after many failures right? Same goes for a quality social connection.