Aren't there cast lists saying who portrayed the editor?
Yes there are. For example, the cast list in Internet Movie Database (IMDB) lists:
David Hollander ... Editor of 'Crimson'
https://www.imdb.com/title/tt0081528/?ref_=fn_al_tt_1[1]
And the IMDB list of acting credits of David hollander (I) also lists him as the editor of Crimson.
https://www.imdb.com/name/nm0390873/?ref_=nv_sr_srsg_0#actor
So there should be no problem, right?
Except that David Hollander (I), a rather busy and well known actor in 1980, was born on August 7, 1969, according to his IMDB page, and should have been only nine when A Small Circle of Friends (1980) was filmed - in March, 1979 according to IMDB.
https://www.imdb.com/title/tt0081528/locations?ref_=ttrel_sa_4
Nine-year-old college students are quite rare, even in movies and tv.
Thus I suspect some sort of error or mistaken identity in the cast lists for A Small Circle of Friends, similar to the way that one reference book listed Adam Hollander (1964-1984) as a member of the production crew of J.W. Coop (1971), even though that was actually Adam Holender (b. 1937), as their IMDB pages show.
So does anyone know, or can find out, who portrayed the editor of the Crimson in A Small Circle of Friends (1980)?
Added sept. 4, 2021.
Paulie_D's answer says that the real life editor of the Crimson at the time portrayed the editor in the movie, and that his name was also David Hollander.
That sounds reasonable - very few person have ever had unique names.
For example, IMDB also lists a David Hollander (II), born May 16, 1968, as a producer, writer, and director, though with no acting roles.
And if you google "David N Hollander, Harvard Crimson" you will find several links to Crimson articles written by David N. Hollander.
https://search.yahoo.com/search?fr=mcafee&type=E211US105G0&p=David+N.+HOllander%2C+Harvard+Crimson
But those articles are dated to the late 1960s and early 1970s. Would David N. Hollander still be writing for the Harvard Crimson at least half a decade later in 1979? Or was the person who portrayed the editor in A Small Circle of Friends a diferent persn from David N. Hollander?