Of course not, parents screw their kids up in multiple ways. Even the good ones. 

I will add that parents do not have to be divorced to create these kinds of environments. My sister's college roommate had parents who were still "married", but who would never be in the same room as one another. My friend had parents who just recently announced their divorce. Her response, "well, you have been unhappily married my entire life, so I'm not surprised." Her father would regularly tell her mother that she tricked him into having children. My friend had terrible issues with men because of this, until something bad happened to her and her dad really stepped up to support her, which helped her to feel more loved by him. 

This is still a high conflict divorce - even if the conflict is not open, so yes - it's damaging to a kid. And in this case, both parties are to blame. Sometimes one parent is high conflict and the other gets dragged along, and sometimes they both are.

BM in our situation was not the yelling and screaming and stalking kind of BM - but she was indeed very high conflict. She did everything she could to interfere with DH's time and turn SS against him. DH wasn't faultless in how he dealt with it, but in general, he did not start conflicts with BM - he could have reacted better to the ones that she created.

I think this kind of high conflict is worse for kids because it's subtle. BM here alway had plausible deniability.

It's just as unhealthy for the kids as overt conflict.  They are still being dragged into the middle of a situation they have no control over and are powerless to change. This often times leads to acting out and children developing control issues. 

I'm sure both are damaging but I would think screaming and yelling is more aggressive and would cause more effects on the child. In my way of thinking, I assume the screaming conflicts happening in public which would cause the kid embarassment, peer ridicule, shame, etc. I would also think that their stress levels would be further up than a covert aggression where one parent is just avoiding each other. Outward aggression just shows such a lack of self control that as a child I would be a ball of nerves fearing how far it would go whereas a covert aggression I could rely on them never exploding but I can choose to deal with it privately.

Toxic parents who manipulate are far more dangerous than the yellers and screamers. Dangerous to both their own children and anyone else in their lives no matter how distant.

The facts are the best tool for beating these types into submission and includes making sure that the kids have the facts as well.

They can't manipulate freely if everyone knows the facts and the truth about them. Bare their ass and make sure everyone knows why.

Look up Parental Alienation Syndrome.