Common, left, and John Legend pose with their awards for best original song in a feature film for “Glory” from “Selma” at the Oscars on Sunday. (Jordan Strauss/Invision)

report released this week by the Ralph J. Bunche Center for African American Studies at UCLA suggests that, by sheer numbers, Hollywood is doing somewhat better on race than in the 1930s. But the most sobering part of the report might be its conclusion. Darnell Hunt and Ana-Christina Ramón have proposed a great set of remedies for how to make Hollywood more diverse. But they rely almost entirely on the willingness of an industry that casts itself as a progressive champion to acknowledge its biases and imperfections, and to make voluntary sacrifices to remedy them.

In 1930, as Donald Bogle explains in “Bright Boulevards, Bold Dreams: The Story of Black Hollywood,” just 2.9 percent of movie actors and actresses were African American, and “the grimmest numbers were for directors, managers, officials in the industry. Of 1,106, only 3 were black.” Now, Hunt and Ramón write, numbers like these persist in Hollywood’s executive suites, but 16.7 percent of film leads, 17.8 percent of film directors, and 11.8 percent of movie writers between 2011 and 2013 were people of color. The numbers are more mixed on television, where 6.5 percent of the lead actors in broadcast shows and 19.3 percent of the topliners in scripted cable series are nonwhite. And in so many of the categories the authors break out in painstaking detail, it’s clear just how far the entertainment industry is from being proportional on camera, off-screen and in its executive suites.

“Broadcast networks must begin to treat the airwaves as a public good through which diverse content promotes profits and democracy,” Hunt and Ramón write in their conclusion. “Studios must cast the net much more widely when they entertain pitches for film and television projects. Talent agencies must diversify their rosters, packaged projects, and their own ranks. The film and television academies must overhaul their memberships. The guilds must better understand their respective membership pipelines and find ways to increase access and professional development for minorities and women. Individual producers and writers must finally accept the notion that having diverse voices and perspectives in the room actually increases their odds for success.”

Well, if that’s all it takes.

I’m being a little sarcastic. It’s incredibly useful to have a comprehensive list of changes that could actually produce different kinds of storytelling. But the nature of these items is also incredibly daunting.

Every single recommendation that Hunt and Ramón make here depends on the goodwill of individuals, businesses and organizations. They don’t even bother to suggest some sort of government action to force the networks to “treat the airwaves as a public good.” Instead, they’re hoping that people involved in this hugely lucrative business will decide to change their professional practices.

The report works hard to build the economic case for diversity. But if these changes are to come about, all sorts of people in Hollywood are also probably going to have to think about themselves differently. And the entertainment industry’s supposed liberalism is probably one of the biggest obstacles to that shift.

If you think you’re a good progressive, then bias has to be creeping in somewhere else in the process. In the entertainment industry, a huge number of people are involved in taking an idea, turning it into a finished product and delivering it to audiences, if you want to find someone other than yourself to blame.

“The talent agencies tell us they are in the business of selling to the networks and studios the kinds of packaged projects they demand. Networks and studios — whose executive suites are almost exclusively white and male — ironically suggest that packaged projects could be more inclusive were it not for overly narrow talent rosters,” Hunt and Ramón write of the sort of buck-passing that is characteristic in the industry.

And if you’re committed to liberal principles and convinced of your own fairness, you can create a dandy little cycle for yourself. Set up correctly, these processes will churn out evidence that women, people of color and sexual minorities just aren’t out there, or just don’t have what it takes to compete. And these talking points will conveniently protect you from any reckoning with flaws in your own thinking or way of doing business.

“Dominated by white male members, the academies continue to celebrate the work of white males as a matter of course, insisting that they do so in the name of talent and artistic merit,” Hunt and Ramón say of some of the dynamics they’ve seen. “Meanwhile, women and minority talent decry being relegated to lower-tier projects or being excluded altogether from industry employment. But the idea that the pool of diverse talent is relatively small motivates employment guilds, networks, and studios to offer an array of ‘pipeline’ initiatives that scarcely impact the overall diversity numbers confronting us each year.” (HBO launched yet another such initiative this week.)

If Hollywood sells us on anything, it’s the idea that people can change. And as pessimistic as I am that Hollywood is likely to experience a mass conversion, I’ve seen some of these changes for myself, particularly on television.

When I first started reporting from the Television Critics Association press tour in 2012, some of my fellow reporters made jokes when I asked NBC entertainment chairman Bob Greenblatt whether the industry’s declining fortunes would lead to the revitalization of diverse sitcoms such as “Living Single.” We have yet to get a majority-minority sitcom about sex, dating and early adulthood, but three years later, “black-ish” and “Fresh Off the Boat,” comedies about families of color, are hits. Shonda Rhimes owns Thursday nights on ABC, and “Empire” is living up to its name on Fox.

But just as Hollywood reform depends on the conversions of individuals and small but powerful organizations, any progress is fragile for precisely the same reason. If you lose a studio head who has reason to pursue diversity in favor of one who prefers another path to enrich her bottom line, lots of other opportunities can disappear in the transition. If Rhimes retires, diversity on television would take a major hit. Shows such as “Empire” and movies such as “12 Years a Slave,” “Selma,” “Fruitvale Station” and “Beasts of the Southern Wild” may be delights. But they’re not a successful revolution.