Okay, I understand what you're saying, and the funny thing is that I totally agree with you on your opinion about no politics rules. I think no politics rules are silly and too broad, too.

So, knowing that we agree on that, let's try to be precise here, because I think you still have some misguided views. Particularly :

"From this, I conclude that the statement “no politics in all major comms is a good thing” is a popular opinion around these parts."

From what I can tell, you're drawing that conclusion based on one post you saw with about 300 upvotes. This is a really flawed line of reasoning. Have you ever studied statistics or cognitive biases? I would really recommend it, because both of these areas show how easily the human mind can look at one recent or mentally prominent data point and fallaciously extrapolate a too-general conclusion from it. Lemmy has many users with many contradicting views, because we are all different people. Yes, there is a group of Lemmy users that wants to see less politics. But for you to conclude from the existence of that group that it is a dominant, or even popular opinion, is a really serious logical error. In fact, it is an issue with abstraction, exactly like you said. You need to be able to conceive of the community in the abstract, not from one single concrete post before your eyes.

Let's look at an actual sample of meaningful, multiple data points: the top posts of the last year.

https://discuss.tchncs.de/?dataType=Post&listingType=All&sort=TopYear

Of the 22 posts on this page, 13 (more than half) of them are political, and many of them deal with unpleasant realities. The other posts are largely about the growth of the Fediverse, which is itself a politically charged topic to most users. From this, it seems clear to me that Lemmy is generally a highly political environment that actually enjoys talking about unpleasant realities.

I know that you had a few direct personal experiences that say otherwise, but this is why the capacity for abstraction aided by statistical thinking is so important.