Why do so many emotionally unavailable people attempt dating?

I’m sure this has been asked before but I’m genuinely so confused by this concept. I’ve noticed a lot of men are very emotionally immature or unavailable but will pretend to not be. I really struggle to understand what the point of lying and pretending to be something you’re not does for themselves? Something I noticed in my love life is that some men feel intimidated by me simply for “having my life together”. I recently was seeing someone for three months and he told me I made him uncomfortable and insecure with how grounded I am, and how healthy minded I was. I asked him what that meant and he said my presence was a reminder to him of how he wished he could be but wasn’t. My last 2 exes also mentioned that they felt insecure and jealous of how I present to people and how I move in life. I personally am not a jealous or insecure person so for me the concept of being jealous with a partner or bf is really odd. Does anyone else share this experience?