I think all the alternatives I remember might have died by now, because instead of consolidating into one site, there were always like 2-3 English-language forums at a time that spread the banned population too thin to keep all of the sites afloat. The biggest and most viable alternative back in the day was called "Counter Factual.net", but I think the site owner had to shut it down after almost a decade due to career or financial burden. All the other ones were more ephemeral and much smaller, more like in-group clubhouse of a minor social circle rather than a proper big active forum consisting of all types.If you know an alternative for Alternate History Forums, I'd be appreciative.
I suppose he's the cause of one of the most annoying traits I see in history discussion, which is moralizing. Usually when you read/discuss history, you want to do so with a neutral, detached view, unless the moral lesson is relevant. But on Alternate History Forums, it seems like they can't have a discussion of anything Nazi or Confederate related without beating their chests about how much they hate those things. They don't just let the history speak for itself. Makes everything they write tiring to read.
Also there was even one alternative site for the handful of people who got banned from AH Forums for being too militant leftist/tankie, presumably by one of the saner mods. This site was called "Between the Waves" (I think the actual URL was that phrase, but in Latin), and it was like some awful clone of RevLeft Forums, except that some of the unbanned lefties and even mods like Calbear were active in that site so it was even more like a secret clubhouse for the lefty types, because the site was mostly invisible to non-members, and registration was by invitation only. It was a very secretive toxic community, because these spiteful lefties would always be talking shit about non-members behind their backs and scheming to get them banned from AH Forums, but word would inevitably leak out and cause a lot of drama. Oh yeah, and I think they tried to do a kind of "ideological paywall" by moving some of their popular content from the AH Forums to this other site, though it probably ended up shooting them in the foot by reducing the traffic to their content overall. I want to say this site ended up dying too, though I have no idea.
These days there's probably no good English language alternative forums. The Wikia site must be pretty big now, but it's not really forum format. There's lots of good non-English forums, but that's not really a solution.