Quick post without any pics; my phone is sooo far away (in the next room).
I just wrestled with my 2015 Accord's rear armrest and I was unable to find any information online about how to remove it, so now I'm posting the secret :-)
On the right-side of the armrest there is a plastic spacer. This is easy to find and remove, and implies that you should now be able to push the armrest 'in' on the right to unclip the opposite side. But it wouldn't move. Eventually I figured-out that you have to pull back the carpeting around the left side and then you'll see a spring-loaded clip holding the left-side in place, too. Pinch to remove and now the assembly can be pushed out, to the right.
It also looked like there was a bolt on the left side and I took a wrench to it, shattering the plastic. I don't think it needed to come off, the assembly was just stuck. But, by then, I was impatient :-)