It's more irony than sarcasm. Me laughing at myself for caring. There are more important issues than this . . . I actually had a

and thought it was too much.
But I am
partially serious. She approves of acts of kindness and Laezel doesn't. For LZ, compassion is a weakness, a warrior's heart should be made of steel.
The hag promises a cure and hag is a pretty darn powerful fae creature. Granted you are right about Astarian's bigger motive and so he
could be speaking out fear but, in my party, Astarian disliked challenging the hag and Shadowheart approved.
Now it could vary by party -- I've only seen the dreams and evil path in videos, I don't enjoy evil narratives but in my party she generally approves of kindness. And there are
[datamining spoilers]
reasons to believe that is a corruption / redemption path for a number of characters. Karlach has lines that praise Shar and that praise Selune. The meaning is uncertain -- this be a line for a "deception check"
Oh and Gale can go to hell. He's buggy and he steals the spotlight from my Tav. He starts by insulting the abilities of my mage and my cleric he goes on to lecture my cleric of Mystra on her goddess and he explains the weave to my mage. Gale, if I didn't fear your aura killing my dog I'd push you off a cliff.
I actually wouldn't be surprised if he turns out to be the Yoshimo character who betrays us at some point. I wouldn't be surprised if he's secretly working for Shar.