My main account used to be on mander, and politics is kinda a general but subtle problem on mander. (I eventually decided not to have a "main" account at all after I realized how much creepy surveillance is on the internet -- little to do with mander's politics.)
Sal tries to prevent the political circus from taking over the instance, but there's a tension because the political circus is increasingly escaping containment and actually effecting people's lives. While I'm not exactly sure what Sal was thinking with this particular incident, I think it's hard to disagree that LGBT has become a part of the political circus and culture war.
Like, let's just lay it out at a very high level: LGBT people, like everyone, are weird. Unlike most other weirdness they're organized and vocal about their weirdness because of a long history of very real persecution. The LGBT community works very hard to "build allies" (make disliking their weirdness socially taboo) because that protects them from further persecution. This is wise in a sense: It's a peaceful mechanism of self defense. The issue is as polarization increases people can become confused about which side is the aggressor -- even if they know overall the LGBT were persecuted, they may view that has historical, or they may think the response is disproportionate, or some other similar view. This frustrates a lot of LGBT people who have personally experienced these persecutions because they know it's not over, LGBT won't be a non-issue anytime in the foreseeable future, and are rather fond of their communities. That said, I think the LGBT community knows it's become a political element. Debatable whether they're political pawns being used to seize power or a political faction in their own right.
I can't tell you whether Sal made the right call or not. I don't know where people should draw the line for apart of politics or not apart of politics, but I don't think it's unreasonable to want to step away from the political circus. Further, dbzer0 certainly doesn't have much room to criticize other instances who choose to moderate their communities, even if you don't fully agree on where to draw the line.
I'd advocate giving @[email protected] some grace with these judgements. They're hard to make, and if nothing else @[email protected] is very clearly a very political account who probably shouldn't be posting on mander in the first place.