steelman, don't strawman. pushback on someone being rude by requesting something they could have looked up doesn't look like "let me google that for you" 95% of the time. it's far more likely to come out as "I'm not sure, honestly. I worked on X, but I didn't really need to get in to Y, so I'm not as familiar. Personally, I'd just do a google search, since I'm a little behind on that."

not rude. not implying anything about the questioner. still the general sentiment of "google it; that's not my job". if you admonish people as being "incredibly rude", you should be talking about things that people actually do with enough regularity to make the point worth making. that is pretty widely understood.