I think the humidity has to play a role in that. Very dry air is not good for the nose even without allergies. This year the spring is very dry and also quite cold in Central Europe which makes things worse.
There's one guy I know who lives more or less in the middle of a forest with both Sugi and Hinoki, and he's suffering a lot. But he still likes it much better there than in the huge city where he grew up. I noticed that among the locals in that place (just a bunch of houses, not even a village) I didn't see anyone else with that kind of allergy.
Yeah I realised that's a little bit of an issue in my theory. Of course if it's very humid I would also expect that most buildings have aircon that's keeping the humidity down and can contribute to the allergies.