Let's hop right into it.
Right off the bat, the biggest real complaint that people have with the film, which is a documentary about the origins of bronies (and Ashleigh Ball's experiences with them), is the error of the origin of the word brony in the first place. Told by everyone's favorite venue authority Final Draft of Everfree Network, the film claims that the word "brony" originated on /b/, and outright denies the accepted origins of the word being a combination of "bro" and "pony" (we provided screencaps of the word's first usage on /co/ in another post).
While this may seem to be a minor detail, the fact that Final Draft's assessment was trusted, even after he declares on-camera that he was not present for the beginning of the fandom, and joined when it was already a "movement", binge-watching numerous episodes, is a lapse in judgement that many consider critical to the core of the film. This sentiment is especially noticeable on 4chan, where it all began.
Beyond those complaints, the majority of the viewers agreed that it is a decent film, and easily one of the best "brony" documentaries made to date.
The documentary is loosely framed around Ashleigh Ball's decision to attend Bronycon, and her first real encounters with bronies en-masse. She mentions how she assumed that they were all perverted beforehand (and that her opinion was presumably changed in the end), and gives a history of her performing career leading up to her work on My Little Pony as Rainbow Dash and Applejack. We get to see some #horsefamous musicians, some EQD staffmember, some interviews with Hey Ocean! (the men in the band are NOT fans of the bronies), some psychologists, some charity work, and of even a whole "Brony Family".
Other things that the documentary features include:
Mandopony demonstrating his "O" face.
Saberspark after eating a lemon
An Associate Producer temporarily removing the stick from his ass
An amateur proctologist who wants you to smell his finger, after having just examined the Associate Producer.
7/10 its was okay. If you have to explain to somebody what a brownie is, use this documentary, THEN use the others, it will probably work better for you.
A Brony Tale is available on Apple stuff and Amazon.