I think a lot of the problem is that our societal expectations of men and women, fathers and mothers, etc. are so different that people have trouble figuring out what all the implications and consequences of their behavior are. So they err on the side of too much censure or too little (for both the Bennett elders). Which, you know, happens anyway; but when you're not sure, really, what the realistic results of Longbourn being entailed away are or what any of the characters could do about it, it makes it a lot easier to miss cues as to what the realistic consequences are.