I think that beehaw guy was more against the “DESTROYED by FACTS and LOGIC” culture, that you see among self-proclaimed “rationalists”, that use half-baked and deceptive statistics and half-truths to mask their hate and pride behind a facade of fairness and logic to be more appealing to normal people.
“Rationalism” is weird and misguided way to describe this for sure tho.
The moderation aspect is mostly irrelevant imo. Most recommended instances allow any content. NSFW and politics are the two major faultlines here.
For NSFW, make a second account on lemmynsfw. Most people on reddit also typically don’t use their main account to watch porn, so this is reasonable I think.
For politics, all general purpose instances are mostly fine, so you probably don’t even need a second account for that.
If you have extremely passionate political views tho, then another account specialized towards your brand of politics is probably needed. Normal people don’t want to read posts romanticising or denying genocides, concentration camps or gulags after all.
Redditors making political posts are likely no stranger to getting banned anyways, and are used to creating new accounts constantly, so having one more account is probably not a big deal.
I personally got banned so many times on the r/AskMiddleEast sub for believing that democracy and secularism are good things and that war is bad. Someone even made a poll there and almost every user of that sub had been banned at least once (even the mods ban each other). That sub made me realize that online politics is a waste of time, but that’s a different topic.