Completely agree... I'm in kind of a similar situation to the fictional MS employee myself but I have also built things on the side. If I received this kind of email from a company I would laugh and then click 'Delete' and never consider them again.
Someone with the level of experience he describes will be hounded by recruiters for all sorts of companies every day - I know because I put my resume online recently and it has been non-stop from both big companies and startups. None of the startups have any issues with my big company experience and neither should the author. So if we're generalising, then from that post it seems to me the author is rather arrogant and a bit deluded about what it takes to work at his startup...
Someone with the level of experience he describes will be hounded by recruiters for all sorts of companies every day - I know because I put my resume online recently and it has been non-stop from both big companies and startups. None of the startups have any issues with my big company experience and neither should the author. So if we're generalising, then from that post it seems to me the author is rather arrogant and a bit deluded about what it takes to work at his startup...