On the one hand "absurd", but on the other hand, if they are claiming asylum on that basis alone, I don't think it is totally unreasonable to have to prove it. I assume if assylum is sought on religious grounds, that the claimants have to prove they are members of said religion etc.

It should only apply to those from countries where it is illegal being gay.

I don't know about that. There are quite a few countries in Africa where persecution of homosexuals happens even though homosexuality is not illegal, they just never prosecute anyone for it. I wouldn't want to have to stay somewhere I'm likely to be lynched just because the people doing it would be breaking the law in the knowledge they'd get away with doing so.

However, I think if you're claiming asylum due to fleeing from persecution,I don't think it's unreasonable to have to provide some evidence you're likely to be persecuted or have been persecuted. Not quite sure what this is in this case...

Those are the countries I was thinking of.