Everything that you're saying can be done with open-weights models by bad people can also be done with closed-weights models by the people who own them. And there is no defence against that, we are forced to trust that the owners are not bad people. Those owners have proven time and again that they are only interested in profit and/or control. They will do whatever they think makes them the most money, or gives them the most control. They will also lie about this.
At least with open weights we know the danger and can do something about it. With closed weights we don't know what's going on.