As you expressed, you see the task as "find meaning in yourself," a concept that can maybe be expressed as "meaning comes from within." This sounds nice! I think what OP was getting at is that this perspective has two problems: 1. It requires you to produce your own sense of "meaning" (whatever that means) that is self-satisfying, AND that works well in the society/community in which you exist; and 2. it is fundamentally self-centered. A hypothesis could be that this perspective seems to most frequently result in a failure to find "meaning" (probably better called "contentment") in anything.
As OP said, faith/religion traditions tend to hand you a set of pre-defined "here's what's meaningful" morals, and these also tend to be skewed towards group value instead of just self-satisfaction. When handed this outlook on meaning/morals, it seems possible there might be benefits - not having to come up with a self-fulfilling sense of meaning that also meshes with broader society, as well as a focus on being useful to the community instead of just yourself.
I personally find the whole "be yourself" / "do what you love" dogma-du-jour to be terrible, and prone to actually resulting in depression and shame. It is at the same time selfish, and self-sabotaging.