What role does a seeker of knowledge have in spreading good morals in society?
He must follow the Book of Allah ﷻ and the Sunnah of Allah's Messenger ﷺ.
And be a good example to others.
He must not command people and forget himself.
"Do you command people to virtue and forget yourselves?
while you recite the Scripture? Will you not reason?"
"O you who believe, why do you say what you do not do?
Most hateful to Allah ﷻ. It means hatred: to say but not do."
So the seeker of knowledge must be a good example himself.
Before calling people he must act upon it himself.
And whoever acts upon it himself is a caller to Allah ﷻ.
Even if he does not speak. When they look at him and his actions.
Then he calls to Allah ﷻ by his actions before his words. Yes.