The Annunciation Catholic Church shooting this past month was perpetrated by a trans person who targeted young children attending Mass.

Being transgender is not relevant to shootings, but there are voices that are trying to make that happen.

My opinion on why it gained traction: the group is already marginalized, is part of a larger, also marginalized group (lgbtq community), and shootings are unpopular, while guns are, so it benefits the speaker to connect the two. There are also narratives floating around that are in synergy with this connection, such as the tragic statistic that trans people have a very high suicide rate, and the false narrative that being transgender is a mental illness.

https://www.snopes.com/fact-check/transgender-mass-shootings...

IIRC there have now been two mass shootings by trans people. Dwarfed by those carried out by hetero, white males; but don't let facts ruin an opportunity to dehumanize a marginalized minority.

Some shooters are transgender, some people try to paint it like transgender people are more likely than others to become shooters.