The same principle applies; homosexuality is prohibited however it's no one's business to humiliate someone who is gay let alone threatening them.
Also if a parent is concerned with regards to their own child's sexuality, they are not to disown them (it is considered cruel and disapproved off to cut off ties with your own family).
Parents have to always be supportive of their children and still take care of them without causing harm.
Islamically the parents can guide them, ask them to pray more etc. and physically the most a parent can do is encourage the child to work or take up hobbies to occupy their mind.
And that's it - no punishment or humiliation, Muslims are told not to mention it again or anything else; they have to leave the child alone, especially if once grown up they still identify as gay - they have freewill.
Countries imposing the death penalty on people who are homosexual like Iran are being barbaric and most agree that it is repressive powers that use Sharia law on women and the vulnerable.
As for your initial question the threats gay Muslims are receiving, I bet it's mainly from their immediate family who are more concerned about how they will be seen by their community; unfortunately this does happen, but the good thing is it is being talked about more openly now with kindness being the motif.
I also know a lot of Muslims who have actively been supportive of Pride events, even hijab wearing women taking photos during work events and happy for it to be uploaded on social media so there is support as well.
I will be honest, I didn't have my photo taken under a rainbow frame for Pride month, not because of my religion but simply because I am straight and it is not central to me.
We even had an atheist who didn't want to have her photo taken in support of Pride for whatever reason and that's all okay because we all have freewill to do as we please as long as we are not hurting others along the way.
I have tried to answer your question as well as I can based on my own knowledge and personal experience, I hope it helps.