I think a pretty good benchmark for "appropriate" is behavior that promotes reasonable discourse instead of reactionary backtracking which. That discourse in Lieu's case did not occur when he was accused of supporting genocide.
But to answer your more general question of who gets to decide "appropriate", that is society as a whole. We, as a society and as a civilization, decide what we find acceptable and objectionable. Right now we have drifted into a territory where a one or two sentence soundbite is considered appropriate to encapsulate complex issues that defy easy solutions despite the soundbite pundits, politicians, and activists that spout them as axiomatic truths, shutting down the ability to have a conversation with anyone who slightly disagrees.
Do you have more insight on this, on how it could be handled better? Or are you happy with the status quo where little conversation but much shouting is the norm?
But to answer your more general question of who gets to decide "appropriate", that is society as a whole. We, as a society and as a civilization, decide what we find acceptable and objectionable. Right now we have drifted into a territory where a one or two sentence soundbite is considered appropriate to encapsulate complex issues that defy easy solutions despite the soundbite pundits, politicians, and activists that spout them as axiomatic truths, shutting down the ability to have a conversation with anyone who slightly disagrees.
Do you have more insight on this, on how it could be handled better? Or are you happy with the status quo where little conversation but much shouting is the norm?