So my question is: is this social phobia, am I just “boring”, do I have a fundamental personality problem, or are these people just wrong?
In a way, the answer is yes to all your questions.
First, I can't tell if it's social phobia or some other psychological condition, nor can anyone else on these forums. You need a doctor for that. However, it is socially-related the way you describe it, and you obviously came to these forums for a reason, so I think there's a good chance that you can find someone else with a similar issue that you can relate to.
There was a point when I realized that people NEVER approached me. I ALWAYS was the one that had to initiate any kind of interaction. This made me
so angry. How come I had to do all the work? What's wrong with me that people didn't want to approach me?
Allowing this frustration to live within me didn't help. If anything it made me bitter towards those around me. The turning point came when I stopped thinking about
why things were the way they were, and started thinking about
what I was going to do about it. So people don't approach me. So what. Am I going to let that stop me from being happy and pursuing my goals and desires? Am I going to let
that be the thing that prevents me from interacting with others? I came to a place mentally where I deeply accepted the fact that others are
not going to initiate conversation with me, and I moved beyond it to a belief that the only thing stopping me from engaging people is my own fear. At least that is something I have control over. That's something I can work on.
Now that I've told you to
forget about why... I'm going to tell you a little bit why

. It's probably because you're sending out signals that convey nervousness and insecurity. These can be expressed in tone of voice, eye movements, and various aspects body language. Just as you are sending these signals without thinking, most people are picking up on them without consciously thinking. Part of the solution is to learn about body language and raise your awareness of the signals you are sending out. The other part is to conquer that fear of being judged, which has far-reaching effects on the way you carry yourself and interact with others.
Do you really think you're boring? If the answer is yes, you've got some self-esteem issues! You are a unique, worthwhile being! You just aren't in tune with that currently. If the answer is no, then other people are clearly just missing out! A lot of people just aren't willing to put in the effort to discover what is unique about someone if it isn't obvious at first glance. Unfortunately that uniqueness is usually not that superficial and it will take some digging to figure it out. Don't worry though, there are lots of things you can do to help. In fact, you may get so good at them that your uniqueness will be brightly visible and attract many more people than you could expect.
For example, growing up I was taught that modesty was an essential quality of a young man. However, being overly modest led me to hold things back and prevented others from seeing who I really was. I was proud of a lot, but I didn't want others to think I was arrogant, so I kept it inside. Bragging is a sign of deep insecurity as you are trying to prove yourself to others. But if you already know your self-worth, you can express your strengths out of a desire to connect with people. If others react negatively, they are probably dissatisfied with something about themselves. To tie this back in to the concern of boringness, you probably know you're not boring, and if others get that impression (mistakenly) it is only because you are not yet expressing yourself with oppenness and confidence.
Other symptoms of social phobia can also get in the way of expressing your true self to people. I'm not surprised at all that people didn't want to be around me when I was insecure and socially awkward. I wouldn't have wanted to hang out with me either. But working on
my fears and working on improving myself has given me the ability to interact with others comfortably and express myself confidently. It is rare that someone doesn't like me after they get to know me

. Now, every once and a while, someone approaches
me first. It's a tiny thing, but it has a big impact on me. It's a sign that I'm heading in the right direction.