well Emma while she has soem of Lady C's bad qualities, is far superior ot her. I'd hardly say that "scolding" them inot harmony and plenty is meant to convey taht she's concerned for them or willing to help them. Wehreas Emma is genuinely concerned about the poor and willing to visit and help them..

And Emma while she is using Harriet to stop herself from being bored, is also wishing to find a good husband for the girl and to make her happy... also as I've said in another post, she encourages Harriet to talk, and to give her views. She's not just asking for fulsome flattery (tho' she does get soem) and agreement from her protegee.. she's willing ot let Harriet talk and have her own views, (so long as the girl in the end comes round ot doing what she wnats)...
Howevvre as regards Bingley and Darcy, I woudld blame Bingley far more for his willingness to be guided by Darcy than I coudl ever blame Harriet for doign what Miss W says.
He is a grown man, with a man's freedom of action, he is not stupid, he has a good education.. he is not all that much below Darcy in rank... yet he allows the older man to make decisons for him about his love life...