I know this was discussed at length last night, but no this is not the same situation as working at an employer. OU is a public school, therefore a government agency. Government agencies are not allowed to punish students for reprehensible remarks. If OU decided to go further and expel students, they very well could face a lawsuit and would likely lose.
How is this even remotely true? The whole University / Free Speech thing was covered a lot during the Charlie Hebdo massacre as part of an intraspective on US free speech. In particular, http://www.nytimes.com/2015/01/09/opinion/david-brooks-i-am-not-charlie-hebdo.html
...The University of Illinois fired a professor who taught the Roman Catholic view on homosexuality. The University of Kansas suspended a professor for writing a harsh tweet against the N.R.A. Vanderbilt University derecognized a Christian group that insisted that it be led by Christians...
People at public universities are routinely fired / reprimanded for what they say and do.