I'd like to point out that he may have made a mistake in assuming this specific post was intentionally being censored, but he wasn't wrong in principle. The censorship at /r/Bitcoin is very very real.
Last year, I took time out of my day to explain why I thought bigger blocks will mean more decentralization, not less in this article.

A link to my article was submitted to /r/Bitcoin and was promptly censored by Theymos himself:

Erik, you may have made a mistake regarding your specific post from earlier today, but the censorship on /r/Bitcoin is alive and well, and is the source of 99% of the animosity that is tearing our ecosystem apart.
Ending the censorship would do more to heal the wounds and move bitcoin ahead than any other single act.
Speaking out against censorship is most important when you aren't the one being censored. https://twitter.com/rogerkver/status/740893340820901889First they came for the Socialists, and I did not speak out—
Because I was not a Socialist.
Then they came for the Trade Unionists, and I did not speak out—
Because I was not a Trade Unionist.
Then they came for the Jews, and I did not speak out—
Because I was not a Jew.
Then they came for me—and there was no one left to speak for me.