It's very, very simple. There always have been about 10% of people who are left-handed - but for a time in history, teachers and society (sometimes brutally) repressed that and forced left-handed children to use their right hand. Once that relaxed and children were left to freely be who they were, the left-handed ratio went back to its historic norm [1].
Obviously, it's been the same for gay, trans and other sexuality/gender-nonmainstream people. They have always been part of human history - from the old Greeks [2] to early Islamic and Hindu ages [3], but as long as there was an heir available for a long time many simply didn't bother to care or looked away in historic Catholic regions. The repression only went really bad with the Nazis, who destroyed the Institute for Sexology [4] and later on with anti-LGBT laws still remaining on the books for decades, then the anti-gay panic with AIDS, and only nowadays public opinion is beginning to relax.
The problem is that Conservatives not just don't get that simple historic fact, they actively deny it based on their morals, and as a result young LGBT people have shockingly high suicide rates (in thoughts, attempts and success [5]).
[1] https://www.truthorfiction.com/the-history-of-left-handednes...
[2] https://en.wikipedia.org/wiki/Homosexuality_in_ancient_Greec...
[3] https://en.wikipedia.org/wiki/Hijra_(South_Asia)
[4] https://en.wikipedia.org/wiki/Institut_f%C3%BCr_Sexualwissen...
[5] https://www.npr.org/2022/05/05/1096920693/lgbtq-youth-though...