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The guy points out to you, directly, that OSX wouldn't work on his machine. You didn't even dispute that contention.
Your solution was, apparently, that he should have stopped using his computer entirely for what? A year? Until Apple fixed OSX so it would be adequate for his machine?
Then you accuse him of misinformation. That's ridiculous. Actually, it's worse than ridiculous.
Gee, Apple shipped a crappy initial version of its operating system that wouldn't work on older machines and made everyone unhappy?
Who does that behavior remind me of?
By the way, admitting that there's ever been even the slightest flaw in Mac software is plenty enough to get you kicked out of the tribe. It's like insulting the baby Jesus.