The OP was asking about LGBT symbols (I prefer to say GLBT). But since you introduced the US flag, some observations.
Of course I honored that flag when I was in uniform for 25 years, and still do, like few other RJ members have. I was the Post Duty Officer on a number of occasions, and personally directed the raising and lowering of the Post Flag, with full cannon salute.
And as the OIC (Officer in Charge) at military funerals, supervised the very formal folding of the US flag over the coffin at the gravesite, and personally presented that flag to the widow or other next-of-kin seated there. Not easy duty, especially because on two occasions the deceased were soldiers from my own command whom I knew, but I chose to show them that honor when it could have been delegated to others.
But a different view of the flag had been given to me years earlier, when I was still a junior enlisted soldier. I happened to be driving past the Fort Knox Confinement Facility when Retreat sounded. That required me to pull my car off the road, get out and render a salute in the general direction of the Post Flag, indicated by the cannon salute and blared music. A more senior sergeant was my passenger, who also got out to salute.
Out of the corner of my eye I noticed the nearby military prisoners in formation in the prison compound surrounded by wire fencing, while their own flag was lowered. I was surprised they had a separate US flag, since most posts only have the main one. But I also noticed that the prisoners weren't saluting, just standing at attention.
After we got back into my car I mentioned that to the other sergeant. He explained the military prisoners were NOT ALLOWED to salute the US flag during their period of confinement. I was taken aback: not allowed? You mean it's a privilege, not an obligation?
That changed my entire view of saluting the flag, which until then I mostly had found a nuisance. I mean, I love the US, I had voluntarily enlisted during Vietnam, after all, wasn't drafted, but all this saluting of a piece of cloth was just a chore.
Now I saw it differently. I eagerly & proudly saluted the US flag from that day forward. And when I became an Officer, I learned something about salutes between the ranks that also changed my attitude, that most soldiers, even many officers, don't understand. But that's another story...