I didn't expect much from it, knowing how Riot handles PR, but this seriously? This is far from a documentary, this a blatant infomercial. They actually could have easily avoided that, by completely leaving out the villainous back story, but sugarcoating it like this? Portraying the Backstory like this, completely ignoring Pendragon and the DotA Allstars incident, is truly hypocritic.
From the "documentary" you can easily get the impression, that riot popped into existence and spent 6 months developing their Champions and designing their kits. Yeah that impression is unfortunately incorrect. Riot got founded and not much later the DotA Allstars Forum disappeared, without notice. Central hub for all things concerning Dota, hero design, balance discussions, ideas for the game, everything. Guess what happened? Those Dota loving Kids hired Pendragon and with him bought all Ressources concerning DotA, since he as the websites Host, had full control over the Server running it. And suddenly not only do we recognize familiar designs in LOL, we also find implementations of the Communities design ideas from the forum, lots of it. Teemo from the movie? Yeah that guy is an immigrant to runeterra, rammus wasn't even changed in the slightest from the forums design.
Nobody could sue anyone, since Pendragon owned the domain and Blizzard owns all designs by the Warcraft 3 Modding License Agreement.
The esports part is actually interesting, this feud has been dying down over the past decade and this was the chance to make ammends with the (now in Dota 2) still active Community from back past.
But riot decided on a dishonest infomercial.