I have been to Serbia a lot and I can confirm that its a much bigger deal when a gay is homophobic there, hence that why Zarko is problaby hiding it, than in france. There was an attempt to make a gay pride around ten years ago in Beograd (the capital of Serbia) and it ended rather bloody. I would say there is a process, but only a very, very small one since then when it comes to LGTB issues. The problem is also that orthodox church has a big impact on society nowadays, and even if people aren't that religious (i don't think serbs are that much actually) they support a lot of the chauvinist and conservative values that are preached by church. And this is, as you assumed, problaby all due to poor education or - against what no nationality on our planet might be immune - pure ignorance and intolerance and the lack of wanting to understand why other people think, feel and behave different to them.