Well, no one cares about Saddleseat, except those rare few who are devoted. People who ride dressage or hunt seat or event usually view it as an inferior style of riding, and many people don't really know what it is, or only view it as what those awful TWH soring people ride. If you read on Trot lately, the USEF doesn't even list it on their national discipline list. They list SS Eq, but USEF doesn't judge Eq, and Eq isn't the only form. That is why I go to www.Trot.org and www.modern-saddlebred.com for people who truly understand.
I have yet to go to a general horse forum where Saddleseat is represented in any fasion. If I have a Saddleseat question, I post where people are sure to know. It is not that "most people don't ride saddleseat" it is that those who do post elsewhere.
Yes, TWHs are ridden saddleseat, but Saddleseat does not equal gaited. American Saddlebreds don't count as a truly gaited breed as only a select few are chosen to be taught the extra gaits, andalusians aren't gaited, morgans aren't gaited, arabs aren't gaited, NSHs aren't gaited, fresians aren't gaited, appy's aren't gaited.... Saddleseat is not gaited, and so the Gaited forum does not suffice for Saddleseat Discussion.
Until our numbers grow, LTS, I'd say we are stuck using the English Riding section for Saddleseat Discussion, or going elsewhere.