Yes he is, here is the relevant quote:
The idea that people in the Midwest (which has a population of over 65 million people similar to France and the UK) are only friendly to white people is pretty crazy.
You quoted a different part. I'm not "laundering" anything, there are multiple statements there. I didn't get the link between "someone is always happy to butt in" and whether or not OP experienced racism in the Midwest, but I am speaking of the generalisation of those experiences to the whole area, which jacobriis covers in the above quote.
> how you can't make generalizations about anyone, when he was the one making a generalization
generalisation in original post:
people are friendly, as long as you look like them
generalisation by jacobriis:
when people say things like this they *often* do so to feel virtuous
unless that's a silent "often", the generalisation is qualified, versus the unqualified generalisation in the first case.
But it's not just that - "generalisation", or specifically "bad" generalisation takes a particular form, otherwise how do you distinguish it from a metaphor? The way the first characterises a specific area based on personal experience, versus the second which talks of "people" in general based on some personal judgment makes them different kinds of statement: the first as an objective account, the second an explicitly subjective opinion.
> that people who say that they experienced X are making things up
No, he said they "do so to feel virtuous themselves" i.e. their motivation, they didn't say anything about the actual truth of the statement. They did not say anything to suggest that they are "making things up".
Given you just accused jacobriis of saying this, I now have to wonder about your original statement: "someone is always happy to butt in to say I'm making it all up" - did they specifically say that, or was that your interpretation?