I don't get the joke.
Is it that it is evil thing to do? (I don't think it is)
Or is it that it's a difficult fight? (which it isn't thanks to height advantage and backstab being an answer to everything)
Tbh, not that difficult when not abusing those. The owlbear does a alot of damage but is still susceptible to spells and said effects so a warlock or wizard can shut her down and Astarion or other characters can bully her.