A person who had made an innocent error generally feels bad about the error and says so.

That's what he did! That is, that's what he did when someone finally got around to asking him about it in an environment where he trusted that he'd be given time to say his side in an unedited manner, which does not include any of the hit pieces you have linked. I believe it's mentioned in his interview with Jordan Peterson, which is the first public interview he gave.

Again you are blaming him for your own error.

This is not a personal attack; this is me pointing out facts of his behavior and reasonable inferences.

First, it is absolutely a personal attack. You're attacking his character and coding ability, which are not relevant to the topic. Ok, technically, you're passively suggesting it via speculative commentary but it amounts to the same thing.

Second, your inferences aren't reasonable, and they're unreasonable in exactly the manner that one would predict based on consumption of inflammatory and deliberately misleading propaganda aimed primarily at smearing Damore. For example, you inferred that he "didn't say anything or apologize," apparently relying on entirely on hostile bloggers to convey that message to you on his behalf. Remember that until this blew up, he was a private individual. He has no platform of his own and no way to offer any response that your chosen sources did not provide to you. So it is completely and utterly unreasonable to hold him accountable in such a way.

Furthermore, the fixation with LinkedIn is unreasonable. LinkedIn profiles are notoriously unreliable and many are neglected and incomplete, since many members are not actively seeking employment (yet retain membership for the social networking). If you had looked at Damore's whole profile rather than just the image, it was clear that not much effort had been put into it. This is consistent with his story that he had not been actively seeking employment when Google offered him an interview based on his Chess playing.

Which brings us to the chess issue. And yes, it seems that Damore stated on his resume that he's a FIDE Master, a term of art that it seems clear that he misused. Specifically he wrote "FIDE Master in Chess (>99th Percentile)". Other claims about chess-playing on his resume seem to check out as far as I can tell[0][1]. So yes, it's an interesting question why does he say that on his resume. I have not found an explanation, but can certainly think of others not mentioned in that stackexchange link, such as he misunderstood proper use of the term. Obviously a mistake, one that shouldn't be made, but nothing like the dishonesty you're accusing him of, especially when you give him no opportunity to explain himself.

Meanwhile, in this obsession with minor errors in an inexperienced young person's first resume or linkedin profile(errors that are easily cleared-up in a phone interview if you actually care), you are apparently giving a pass to someone who anonymously leaked a co-workers' fair and well-reasoned internal posting to outrage media to encourage hit pieces and start a witch hunt. ... which ultimately resulted in the employer being hit with a ton of negative press and a high-profile lawsuit.

So, no, your inferences are not remotely reasonable or appropriate by my estimation.

[0] http://www.uschess.org/results/2003/nya/?page=WINNERS&xsecti...

[1] I don't know what "Board 1 and Conference Champion" means, and "Rise of Nations" is a PC strategy game.