Earlier quoted context omitted.
I'm sorry, but are you actually comparing Nazi symbolism to the LGBT flag? This has to be sarcastic, no?
A swastika, an LGBT flag and a hammer and a sickle are all political symbols. I found it funny admins only banned one of them.
The hammer and sickle is more comparable; it is indeed banned in a few (mostly post-Soviet) countries. But I've never heard of the hammer and sickle running into the same problems regarding hate speech laws, which was probably Reddit's focus here.
Though politics are involved, the LGBT flag represents identity and is not very comparable to major political movements with dodgy human rights records, or a symbol with a history of being behind "hate speech".