From the telegraph article:
The LGB Alliance naturally tries to advance its work with the media. One important media player is Thomson Reuters, which describes itself as “the world’s largest news and information-based tools to professionals”. Thomson Reuters has a philanthropic arm, the Thomson Reuters Foundation, which works, it says, “to advance media freedom”, identifying disinformation and “the resulting erosion of public trust in news sources” which “undermines accurate and impartial journalism”. It is part of the Trusted News Network.
An offshoot of the Thomson Reuters Foundation is Openly, which describes itself as “a global digital platform delivering fair, accurate and impartial LGBT+ news to a world that isn’t”.
The LGB Alliance has for some time felt frustrated by the lack of coverage it receives from Openly. At the beginning of this year, Kate Harris, co-founder of the LGB Alliance, wrote to Hugo Greenhalgh, the editor of Openly, asking for a meeting to establish a better news relationship. (An earlier attempt at engagement in 2020 had failed.) Mr Greenhalgh initially agreed to a Zoom call but then fell over a pavement slab and postponed. He then postponed again, explaining that his boss was sending him to Ukraine and that he had a lot of other things to do.
Cath Leng (ex bbc) has deleted some tweets I saw on this but has said in another post that charitable status is important for journos to be able to quote or work with an organisation.
So mermaids attempt to remove lgba charitable status could be seen as an attempt to deny the media access to these differing views.