They're not calling those specific things abuse, but if you've lived in an emotionally abusive home they're highly recognisable moments. It sounds like you're coming at this from a slightly too literal frame of mind.

Where is the abuse or neglect of a father being quiet during one dinner?

The implicit presumption is that if someone is quietly fuming now, they'll become physically violent later. Or verbally abusive. Or neglectful to the point of harm (refusing to feed a hungry child or change a dirty diaper out of spite, hunkering down in front of the TV and leaving the kids to put themselves to bed, etc).

But the flip side of this is a child seeing a parent in distress and trying to accommodate/relieve their pain (as opposed to a child blissfully unconcerned/unaware of the parent's stress antagonizing them).

Again, I do think I know where this is coming from…

YMMV. It's very hard to discuss a real historical situations when you're working from a superficial description or hypothetical implication.

I think where OP's narrative goes wrong is in describing tense moments in the house as a parental failure without looking beyond the immediate tension. Relationships aren't some morality play or ethical binary, with a Good Parent and a Bad Child or visa versa. Sometimes you've just got an overwhelmed parent and a child thrust into more responsibility than they're prepared to handle, as a consequence. Or a sick parent being cared for by a child. Or a grieving parent who is being comforted by a child who doesn't really understand what is going on.

A friend of mine just had his father-in-law pass away, and - of course - his wife was devastated. He had to take over all the household affairs while she worked through her grief. His kids, in turn, had to cope with a mom who was emotionally unresponsive and a dad who was juggling twice the workload. I've gotten a few curious anecdotes about how they've been processing the trauma. A lot of it has them replicating the care their parents showed them back onto their parents (as best a 2 year old and 4 year old can).

This post is like describing a baseball butt slap as sexual abuse…

I think even that is too specific. I'm more reading it like someone describing a response to the Jaws soundtrack. Are you excited or intrigued or terrified or all of the above? Kinda depends on how you feel about seeing a big shark.

Emotionally abusive parents is what is described, you become very sensitive to nonverbal clues of your parent(s).

It's not exaggerating, you really get to live around their personal tripwires. And then assume everybody else has those, which makes it hard to trust people.