Against collective guilt
An organization I'm a member of in Hong Kong recently hosted a joint event with a national chamber of commerce and it caused a bit of a kerfuffle. A portion of our membership had ethical or moral problems with conflicts that said nation was or has been involved with. While I certainly sympathize with said members' views on the conflict, I also don't believe in collective guilt...especially when it comes to nationality. Very few people choose the nation of which they are citizens and most of them have very little control over the policies of these nations.
I'm a former American and I disagree with pretty much every conflict the USA involved itself in during the three and a half decades of which I was a citizen. But I didn't choose to be born American and nor did I start or support any of the conflicts the country involved itself in. While I took the relatively rare step of leaving, I'm entirely aware that that has made zero difference in the foreign policy of the country. It's just not realistic to expect people to immigrate or seek out new citizenships just because the place that they were born has objectionable policies.
There's little point in ostracizing fellow Hongkongers who are nationals of nations we might not like. Hosting an event with another organization isn't an endorsement of the policies of the nation they are associated with. A nation's guilt is not our own.