I actually saw the tweet in question last night, and my reaction was the same as John Wessling's. Despite Rashad Butler's initial reply to Wessling of "not at all!", sure enough, Butler has deleted the tweet.
Try as he might, Butler can't unring that bell. Thus, it's hardly a surprise that Jerome Solomon wrote about the episode in today's Chronicle.
Solomon's analysis sums up the situation as follows:
This isn’t an issue of free speech. Fontaine, Whitlock, Martin and Butler aren’t facing public floggings or jail sentences for their words. They are free to say whatever they like.
Free speech doesn’t mean you are free from negative reaction by people you offend (even if it seems irrational to you) or free from discipline from an employer, who doesn’t like the negative publicity you brought on the company.
Do you think the Texans will fine or suspend Butler?