It seems like it's becoming a bit of a no man's land.
The more vocal Third Rail people seem to congregate in 236. I don't know if their tickets are all there or if that's just how it ended up, but I tend to see 236 referred to as "the" TR section.
Hearts of Oak are in 238, so it gets a lot of love as well.
So, of people who originally bought tickets in 237, you have a chunk migrating to 236, and another chunk going to 238 (points at self) or some other section they've connected with. Assuming I'm right about that, it's not really a surprise that 237 can seem quieter or less organized.
Given all this, I'm curious and nervous to see what happens with the section assignments next season. Will two sections still be reserved for TR even if they're - in a sense - only filling one? Or will the FO not see an issue, since both sections seem about equivalently full? What happens to people in 236/237 who are no longer in TR, but as Founding Members should have right of first refusal on their tickets? Etc.
(All of the above is my experience/opinion/assessment and isn't meant to represent any group.)