It should be patently obvious to everyone that no amount of argument, or persuasion will effect any change in Conrad's opinions.
I believe him to be mistaken, as (evidently) do almost all the other contributors to this thread.
And yet, this thread keeps on floating to the top of the pile. (And yes, I am aware that I have just floated it back up there again.)
The songs people choose to sing in public reflect their upbringing as well as their own personal opinions and mature life experiences.
I live in Glasgow. For historical reasons, Glasgow is about the only UK mainland city apart from Liverpool, which has been subject to echoes of the tensions that polarise the communities in Northern Ireland.
For myself, and speaking for the other members of the folk club I most regularly attend, we regard ourselves as "mixed company". Apart from one or two people who I know well, I neither know nor care what "allegiances" people may feel. But, because we are mixed company, we refrain, all of us, from singing anything that could offend, or inflame, other members. There are no rules about this... no-one has ever said it .. no-one needs to say it... we gather together to sing for fun.
I used to run a pub in Glasgow. And despite the image that is often portrayed of "a city divided", in fact, when in "mixed company", people are careful not to give offence, because, IN this city, offended parties often respond very vigorously indeed. So people get along. Another example. Apart from a few pubs which are blatantly partisan, in most pubs in Glasgow it is forbidden to wear scarves, or strips supporting your football (soccer) team. The sign usually says "No Colours!". - which has spawned a few arguments and gasps in visitors from the States ... it's an attempt to reduce possible causes of friction.
The reason for this is that this city is shared. It is shared by people of many origins - Scots, Irish (same thing really), English, Jewish, Italian, Indian, Pakistanis, Chinese.... etc..
We share it. We are all entitled to live here without being offended or threatened. (And that extends to singing or being sung at.)
In summary:
I probably won't ever sing songs of either (Irish) tradition - not any that refer to conflict or division.
But it's my choice. Other people make different choices.
They are entitled to.
Cheers.