IC: Anything Pathfinder 2e
It's also worth bearing in mind that at this point in the realm of virtual tabletop, play-by-post isn't the most popular option. I suspect that if you looked elsewhere you'd find significantly more choices.
People also still have a great deal of time, money, and system knowledge invested in the first edition. With newer editions being the current hotness when it comes to finding a table elsewhere, I suspect it's easier for people to look off the beaten track.