To be fair “have a beer with” is about trust.
If I can’t sit down with you, have a beer, and enjoy myself, I can’t trust you. A president is going to encounter unknown challenges and I need to trust them to solve it.
That being said Trump fails that test immediately. There is no version of “having a beer” with Trump where I could trust him.
Biden however? If you asked the average American what they know about Biden one of the top three answers is “having a beer”, it’s called “grabbing an ice cream” but the principal is the same.
I completely agree, it’s a simple metric and one that charisma plays a role in. If that’s all you use to judge someone it’s going to be a small part of the story.