Its because it comes from the same political faction. In general people are open about A when A seems palatable, and openly B when B seems palatable, but they almost never admit to do that when its obviously wrong to do so.
That is the rational part of the fallacy, even if these are different sets of people you can still tell they are biased since they never appear in the threads where its obvious they are in the wrong.
For example, lets say in a thread where a white cop shoots a black guy you find a lot of republicans say "this is just statistics, nothing to see here". Then in another thread where a black cop shoots a white guy republicans pour in and argue this must be racism and we should investigate! Maybe it isn't the same set of people, but its still a strong sign of problematic bias that they only choose to speak up in those particular threads and not the others.
Every political side everywhere does this, and that is why people started calling that out.
But nah, clearly they're all goombas.
I think it's very silly to make the argument that "groupwise hypocrisy" is not a fallacy in such a conversation. In politics, the reality is that people have to form coalitions with people with whom they don't agree on everything, and non-political groupings are even more non-sensical, often holding people responsible for the opinions of other people who happen to share things like inborn characteristics. It's especially ridiculous to explain this with this idea that people are engaging in some kind of elaborate coordination to argue with you on the internet. Yes, some people, and indeed political parties, engage in that kind of behavior, and if you think you're arguing with something like a botnet, there are larger considerations to make about what you gain as an individual by trying to engage with such a machine at all. If I believe I'm arguing about the merits of an idea with an actual person, and I find myself reaching for something like "your group is collectively hypocritical on this issue" to make my argument, this is cause to reflect on whether I actually have any real arguments for my position, as that one is... well, essentially meaningless
I think you're trying to invoke what's commonly called a "motte-and-bailey" argument, where people argue for a maximally-defensible position when faced with serious criticism, but act as though they're proving a much less defensible version of their argument, often including a nebula of related ideas, in other contexts. This is something individuals and coordinated factions absolutely do, but again doesn't really support treating any grouping you want to draw of some kind of collective hypocrisy. Even assuming we care about hypocrisy, it seems like this kind of reasoning about nebulous groups that don't explicitly coordinate would allow making that argument about any position in any context, depending on how you draw the boundaries of the group that day. It's well-understood that you can go on the internet and find someone who believes just about any crazy thing you can think of, or find someone who makes the argument for any position poorly.
it concerns you because you have a good authority over your spoken language, and like most people with those skills I presume the language flows easily from you.
that ability isn't guaranteed, for a lot of people expression is tough, and those people felt equally alienated when confronted with an essay of word salad about why their opinion is wrong.
An LLM is a tool. In the 90s I would read columns and editorials about the disgusting faux pas of replying to a wedding invitation via such a cheap trendy medium like internet e-mail , now you receive death certificates that way.
It's not all bad, simpletons can use LLMs to have the critiquing essays turned into 5 word ELI5 statements that they can become enraged over once all the nuance is stripped. That's fun!