An acronym/initialism that gets too long becomes a barrier, rather than aid, to communication. It almost becomes encryption rather than a concise summary of what is being discussed. Some of the extensions to LGBT go way past this point. How is understanding aided when you have to explain the initialism every time you use it? Who decides which order various identities get placed in?
There should be a better term, rather than trying to include everything specifically, go for a broader term. That’s the only way to actually cover everyone without full page strings of seemingly random characters. Ideally not a reclaimed slur- while I have no issue with the concept of reclaiming slurs, that’s always going to be controversial among some parts of a given community so something should exist that doesn’t run into that issue.
I wish I had a good candidate. I do like reclaiming “queer” as an umbrella term, but as I said, that’s going to be controversial in some quarters, especially if it’s something cishets use to refer to us(which I’d have some issues with with ‘queer’).