Jaime Christley’s review published on Letterboxd:
I'd like nothing more than to plead guilty to disliking this film for reasons of Welles loyalty - which, if you know me, I expect is something you already know runs very high for me and repels most small arms fire. No, the antagonism between Welles and Mankiewicz in Fincher's movie is, generously, greatly exaggerated by many of the early previews, the impressions gleaned from trailers, and subsequent publicity-adjacent clickbait articles. The washed-up writer on a long bid for a soupçon of redemption is kept both geographically and circumstantially separate from the "boy wonder" Welles (I've read some critics say Tom Burke gives a bad performance, but I disagree; he soft-pedals the impersonation tics and is otherwise perfectly satisfactory) for almost the entire movie. Furthermore, while rivers upon rivers of bad blood are flowing under, around, and through California during this era, as concerns Welles and Mankiewicz, theirs don't really commingle. Contrast this with Mank's (Gary Oldman) seething contempt for Irving Thalberg, his nose-thumbing at Louis B. Mayer, his mistakes and gaffes with family and confederates like his brother Joseph L., and, with the load-bearing beam of conflict, the windmill he tilts at by the name of super media mogul William Randolph Hearst, which, ..... not enough room here but suffice to say if you watch Citizen Kane, Mank in Mank presumes the mantle of Jedediah Leland's disappointment with Charlie and that's maybe 60% of the story, but it's the 60% that gets enunciated in a long slurred show-stopper towards the end of the picture.
So yeah, the idea of a movie trying to get a rise out of me due to my esteem for Welles and (more importantly but we'll get to that) his art won't play. Richard Linklater gambled big with my emotions with ME AND ORSON WELLES (an excellent film, for the record), which momentarily made me hate Welles for firing Zac Efron. Yeah, it felt just as weird to type that as it must have been to read it. Anyway, Fincher's picture simply isn't a Mank v. Welles kind of thing.
Nor is it in the film's remit to litigate Orson Welles as a failed or vindicated or pretentious or sublime or what have you genius. There's no expressed or implied disrespect towards let's say F for Fake, The Other Side of the Wind, Confidential Report, or Touch of Evil. I'm even game to concede that it's neither here nor there that David Fincher is as ignorant of Welles's post-Kane masterpieces as, let's say, the people who made The Artist are ignorant of late silent / early sound cinema. Fincher's on record for tossing around some careless bad-faith bullshit about Welles, to the tune of: Mank wrote Kane, RKO paid for it, Toland filmed it, Welles took credit for it. None of that slander is material to Mank. It's a lot of smoke. Compelling smoke, but smoke. Put another way, the film is almost totally indifferent to Welles, except as a late-arriving spectre, no more than half a Harry Lime.
So what's my problem? Simply put, Mank is David Fincher playing proudly to his weaknesses. His famously cultivated obsessive-compulsive craft, I find here, maybe for the first time ever, almost completely inert. I don't attribute this to some kind of negligence, rather a wrong-headed, right-spirited love; he's filming a screenplay written by his later father, Jack Fincher. It's a "love letter to screenwriters", that kind of thing. Fincher (David) directs and shoots his dad's script like it's a great work. But it's not. It's lousy. Mankiewicz's life story, as Eric Roth-ified here, is a Gump-ian saga, its telegraph lines posted regularly to encounters with key figures in the screenwriter's public and private life. The dialogue is often flashy and colorful and oblique, but it's nevertheless the kind of period recreation where someone will say "Kate Hepburn, why haven't you heard, she's box office poison!" while some royalty-non-liable ersatz "Sing, Sing, Sing" drones softly in the background.
I appreciate the challenge of the project: you want to double-tribute A Screenwriter (your dad, who wrote Mank; Mank, who co-wrote Citizen Kane), doff your cap to the profession as it rose and fell during a bygone era, and illustrate the guts and viscera that preceded a great masterpiece of the US cinema (pinned to one man's face-first self-immolation in California gubernatorial politics in episodes that would augur the complete annihilation of leftism/progressivism/socialism in the culture at large). Maybe it doesn't help that the biopic, the anti-biopic, and I guess the neo-biopic? have all been stone dead for better than 30 years. Mank is a bore, but within his withering carcass beats a heart of gold, tarnished maybe, but still there's a little glimmer. Long-suffering wife, check. Hard-truth-delivering yet affectionate brother, check. Young mentee played by one of the new Lilys, check.
As I alluded to earlier, this is the first time I thought that Fincher's images were attractive, occasionally dazzling, but never particularly compelling or interesting. I can disassociate his verbal gaffes in promo interviews for the movie and, at the same time, conclude confidently that his attitude in the largely delusory struggle between director and screenwriter - which seems to be along the lines of, the screenwriter makes the movie, the director & everybody else merely shoot it, serving at the writer's pleasure, helps to ensure that the movie is not only flat and empty and tiresome, but it's that way in order to make A Statement.