I’ve encountered an interesting type of exchange and I’ve figured out what’s going on.
Suppose someone makes a negative accusation of you without explaining how they came to their conclusion. You call them out on it. And they reply “I’m just making observations, don’t blame me.” What’s going on?
They're insinuating that their conclusions (aka "observations") are not affected by their thinking and instead they're getting their conclusions directly from reality. So they're saying that it's not their fault (not their responsibility) that they made those conclusions. They're saying that it's your fault that they made those conclusions. They're denying responsibility and they're trying to shift that responsibility to you.
These are also the people that sometimes claim that "perception is reality", that if people perceive something, then that's what happened. But they don't apply this idea consistently. They only apply it when it's convenient for them, when it happens to agree with whatever bias is currently active in their mind at the moment. It's not a surprise that they don't apply this idea consistently, because it's impossible to apply consistently. Different people perceive different things, due to our fallibility and that we don't all make the same mistakes, we don't all have the same blindspots.
This is not how things work. They're contradicting basic things known about the scientific approach. All observations are theory-laden; our observations are affected by our interpretations of the sense data that we receive from reality. And those interpretations are affected by our ideas, which includes our biases. So if someone has a bias related to the thing they're "observing", and if they don't do all the necessary steps to combat bias, then their "observations" will be tainted by their bias.
This is a matter of honesty. People think honesty is a trait or something, but that's not true. Honesty is work. If you did the work, then you were honest. If you didn't do the work, then you were dishonest. What work? The scientific approach. Recognizing that you could be wrong and taking all the steps necessary to make sure you account for that possibility. It means giving explanations for your conclusions and submitting your explanations to criticism, your own and that of others (peer review). It means making sure to keep your conclusions tentative, always ready to receive new info and update your conclusions if warranted.