Are moms always right?!

My mom doesn’t like my FH. I have asked her to be open minded, he’s changed a lot since they first met him, and it seems she’s changed her rude ways. There’s nothing I can see wrong that she says and she has been known to be manipulative and materialistic. Her only complaint was “he doesn’t have a job and he doesn’t talk much, I just want you to be comfortable and happy in the future” everything else she said she “couldn’t tell me”. I’ve tried to have adult conversations but haven’t gotten far. Both parents have warmed up and welcomed him better than at first, but I still feel the coldness towards him. I’m the first child, I get that they don’t want me to leave quite yet and that is hard. I saw someone on here say “mother’s instinct is always right”, but I don’t know if I believe that, is mother’s instinct ALWAYS right? Does that mean in the future it will just fall apart for me every time she says it will? Any other adult, individual decision has been met also with anger and resentment, if that gives it some more background. I’m not leaving my FH if I’m happy just because she says she’s not happy.

Sorry needed to clarify. He has a full time job my mother just doesn’t like the job. Don’t know why. It’s just a labor job.