Those opinion pieces you linked are basically just conservative clickbait hyperbolically claiming “segregation” for rhetorical purposes.
For example, colleges do not have separate official graduation ceremonies for students of different races. Many minority student groups on college campuses hold their own additional ceremonies/celebrations for their members, as do, e.g., some honor societies and some fraternities and sororities. But the actual official graduation ceremony includes all members of the graduating class.
Referring to that as “segregated graduation ceremonies” is pretty ridiculous, but par for the course for this sort of “oh noes the liberals are the REAL racists!” propaganda.