Many workplaces have the “potential” to be great. Few rarely live up to that potential. If you’ve been contemplating leaving unless things change, try to be clear about what will make you stay. Discard any notions about what “should” have happened or what was “owed” to you or how you were “lied” to.
Ask yourself “what would it take to make me stay?”. Once you have the answer negotiate to achieve that. Only that. Or leave.
When negotiating make sure to only talk with decision-makers. You are wasting your time with anyone else.