I personally doubt that Louise is very bothered about LGBTQ+. I doubt she has ever thought much about it. She has apparently been represented long term by a top publicist and personal friend, Simon Jones, who also represents Ant&Dec, Dannii Minogue, Matt Lucas and more. I had wondered why, over the years, we have had endless stories about Louise, how she ditched her husband, how she wanted him back, about her new man, and and and. (OK I should not flick through the Mail side bar of shame, but hey.) I had missed out entirely on Eternal, and Louise seemed to be just one of those people famous for being famous, with a slight curiosity about why someone in their 40s would ditch husband and family for a (non) career.
I doubt she is doing anything more than virtue signalling. You believe something because everyone around apparently does, and they tell you it is the right thing to do. You don't think it through, if your object is fame and "success". We all know what happens to people in entertainment/arts who defy.
She has crossed a line here. Even if she is too self-absorbed to understand that that press release carried risks for her former colleagues, the people around her and advising her would have known what they are doing. All power to the sisters. They sound a lot more talented and interesting.