You think they will be that closed off?
Yes.
There are some things if not learned early-on won't easily be learned later, like social graces, manners, logic, critical-thinking, and even spelling. People become calcified in their habits and any attempt to suggest improvement is seen as a hostile incursion.
The smart exceptions out there welcome advice, but about manners? Saying, "Let me teach you some manners" is code for fighting for many.
Why is it that so many people react with hostility when we try to offer valid spelling correction? Same thing, only far more mundane. Manners is a much lower-level skill, as in much more fundamental to one's character and thought process.
Think about the mindset of a ghoster. They don't care about social graces, closure, communication, etc. Ghosting people who approach disrespectfully is valid, such a ghosting disrespectful lowballers.
I would never ghost someone who is making sincere and polite offers, even if their offer is too low. Part of the issue with lowballers is their reckless, aggressive, and/or disrespectful approach. They think they're being efficient, but some won't want to deal with that kind of personality.
Hell, isn't this why most of us refrain from cursing when first meeting someone? Even a period at the end of a word can be seen as rude, or typing in all caps.
Example, consider the difference between these responses:
No.
no
NO
NO!
No, thank you.
Each will evoke different subtexts or even hostility, especially in Gen-Z who are more sensitive to the full stop.
In my view, ghosting polite communication is a character defect, a trait I see in people who view others as impediments or objects of opportunity. If we observe criminals, they treat people as objects too.
Social graces are a way to quickly build rapport and trust, and some people we meet become friends.