Maybe. I did not even know about that post at the time - and I still am not sure that I do even now - and to similar posts people seemed to have mostly responded that they too were not aware of things. People might be a lot lazier than you are giving them credit for!:-P e.g. people coming over from Reddit simply hop onto lemmy.world without giving a single moment's thought to any considerations like spreading things out across the Threadiverse - which for someone's first instance choice I do not criticize (at least, back then it was more understandable), since they can best learn about the Threadiverse by having joined it, and then make a different decision later on.
Nowadays, lemmy.world makes up roughly a third of the Threadiverse (14.2k / (35.2k + 2K PieFed + 0.7k Mbin). Over on r/RedditAlternatives, people like Blaze primarily direct new users towards feddit.org (iirc) or discuss.online (for people in the USA), or more recently PieFed (both are generalist instances and avoid issues with having the name "Lemmy" as part of it). Setting aside any issues with Lemmy.World's moderation practices (which personally I think are mostly overblown... though perhaps not entirely), it is just good practice to help spread people out a bit.
Though back then, Lemmy.World made up a whopping ~80% of the Threadiverse. So having "mostly lemmy.world users" posting was the experience shared by pretty much every community across the entire Threadiverse (back then, mainly just called Lemmy, as first Kbin and then Mbin were always barely noticeable blips with <1k active users except the very first month it started).
I do not doubt that there was additional specific drama there - several of those mods are kinda known for being drama lamas:-P - just adding this background context to it all.