The broader question being asked is, if this is the situation now, what else may be enacted before the conference. Things like, what if there's a foreign gay attendee who's blocked at airport security?
Harassing a gay person at the border would risk 2 while not contributing to 1.
You must be kidding, right? Even though Poland is currently ruled by right-wing minority, and some of these are mindless assholes, any kind of real sexual discrimination is illegal and persecuted. If I was discriminated against at work because I'm gay, I'm in for good compensation as my case is pretty strong.
Your reasoning isn't too different from the above. Gdańsk is a liberally-governed city.
Even if Gdansk is liberally run it sends a signal to legislators that policies effect revenue and gives them a reason to push back that avoids moral arguments. That being said, I think it cedes the moral argument to the opposition, but any fight like this has multiple fronts.
The reasoning is very different from what you wrote. Surely, you see the difference.
You're accusing them of bigotry without weighing the clear higher value here, which is: solidarity for the conference goer who might be vulnerable to persecution because of these policies.
That LGBTQ people attending the conference ought to shut up and put up?
That these policies are harmless, and therefore justifiable? (I think we can be certain the only justification for a policy like this is the intent to cause harm, because why make them a thing otherwise.)
"a group of people sharing the same culture, history, language, etc.; an ethnic group."