Could folks please stop giving advice on that unless there was a time when they had trouble with that, and know specifically what they did to overcome it?

You don't need to control others to get what you want out of an interaction. In fact, letting go of control is a key step. It also paradoxically increases your influence (in non-toxic environments.) Reading Morendil's reply seven times is recommended. That was golden.

there was a time when they had trouble with that, and know specifically what they did to overcome it?

I do happen to meet that criteria, but there is more than one challenge that I (and most people to various degrees) had to overcome when starting conversations with random people, some of which required simple behavioral changes while some required fundamental changes in beliefs.

Is changing your beliefs a skill that you have developed? For example, did Juggler's influence change the way you think about social dynamics? Do you have the ability to actively question and update your model of yourself and your environment based on introspection and self awareness? I'm not making a snide insult here. Developing that skill is central to how I overcame those difficulties and, in various guises, what many social skills and personal development gurus will recommend. It does involve asking ourselves questions that we really don't want to hear.