I'm more exposed to American conservatism. And even here I barely understand it. I used to be Christian, but I left the religion before I realized I was bi, and before I knew genderfluidity and trans people existed.
I guess I'd have to know why individual religious groups, countries, cities,(etc...) have anti-LGBTQ beliefs. Maybe there are no blanket statements that properly address it for the entire world.
A lot of conservative ideology is to be nostalgic for an idealised version of past hierarchies. If we could just return to the social relations of the good old days, all the problems of present society would be solved. If your culture did not traditionally accept openly queer people, the presence of LGBTQ people becomes a problem to be solved in the reactionary mind.
One of the other important "traditional" hierarchies to most conservatives is that of gender which can explain the rage many of them feel towards queer people, especially against trans women, who are seen as subverting gender roles.
Conservatives don't have to be openly homophobic though and societies can develop in ways that produced superficially pro-LGBT reactionaries. Nordic societies are less tolerant of open homophobia than many other places and anti-LGBT sentiment doesn't translate into political power.
Instead the reactionaries there have adopted what can best be described as rainbow racism. Although they drag their heels whenever anyone talks of expanding them, the conservatives there have adopted a superficial support for LGBTQ rights but have done so in a reactionary way where being accepting of queer people is added to the list of virtues that makes the civilised Aryans superior to the savages of "the jungle".