He is not pretending to be an arbiter but speaking generally to what many people, including myself, believe. And in any case, you attempted to refute what you reduced down to his own subjective opinion, with your own subjective opinion.
Working against software patents is part of the larger essence of OSS, and it was just a specific example of it. If you are for software patents, and somehow magically "for" open source, then you aren't really "Open Source" you are just hiding behind that facade so you can now accept free labor when it serves your purposes.
So, in that regard, it isn't difficult to see where the negative sentiment is coming from in regard's to the recent media blast of the "new Microsoft."