Is there any word referring to people who sit and comment rather than act.
Example: Reading morning newspaper headline, sad news and discuss over tea rather than act and do something toward it.
If they are reading and commenting about it after the fact, I’d call them “Monday-morning quarterbacks.”
If the event is still occurring and they don’t have the skills, means, and/or opportunity to do anything except comment or complain, I’d call them “Armchair quarterbacks/generals" or perhaps even “kibitzers.”
Finally, if it’s still occurring and they do have the skills, means, and opportunity to help but lack the enthusiasm or concern to extend their involvement in the issue beyond that of merely commenting on it, I’d call them “apathetic/complacent/indifferent (and/or if the consequences of their inaction so merit, even)/depraved-heart/heartless observers.”
Slacktivist seems to fit (especially online), if their comments are intended to get people to agree that something is bad but they don't actually do anything about it or contain a "call to action" besides "Like this post".
A possible description is passive spectator:
a person who looks on or watches; onlooker; observer.
not active, but acted upon; receiving impressions or influences; not actors in the scene.
The Free a Dictionary
An obvious candidate is kibitzer; "A kibitzer is a non-participant person, offering (often unwanted) advice or commentary."
The term is standard in contract bridge.
And yes, the verb is "to kibitz".
You can try these words:
Unconcerned: not worried or not interested, especially when you should be worried or interested
Bystander: a person who is standing near and watching something that is happening but is not taking part in it
Uninvolved: Not connected or concerned with someone or something, especially on an emotional level
One expression is the "peanut gallery" which means "A group of people who criticize someone, often by focusing on insignificant details."
It's not perfect, but this is what I came up with:
chiefly North American- Criticize (someone or something) with hindsight:
no one should second-guess police officers whose lives are on the line
In a workplace, if it is negative unhelpful comment, we call these dementors. They tend to swarm and suck the life out of situations.