I haven't watched many of them, but the ones I have I've enjoyed. Recommend some great video game documentaries. Here are a few that I'd recommend.
The Smash Brothers: It's a documentary that outlines the Super Smash Bros Melee competitive scene from the early 2000s up until the early 2010s. I am not a competitive smasher, I love the game, but I am no even a fraction as good as the people in this documentary. Even if you're not a Smash fan I'd definitely recommend it since it outlines some very interesting rivalries as well as some pretty interesting people. The full thing is like 4 hours long, but luckily its broken up into chapters. It's also worth noting that this documentary has a massive early/mid 2000s vibe to it which is incredible. It's up on youtube for free.
Chasing Ghosts: I don't have much to say about this since it's been forever since I last watched it. Pretty much it's about the Twin Galaxies Arcade and the crazy competitive arcade scene in the late 70s and early 80s. You also get a lot of insight into people like Billy Mitchel, Walter Day, and several large video game personalities from the time. You also get interviews with some of the guys who were the best at arcade classics like Pacman, Missile Command, Donkey Kong, and several others. Definitely, definitely recommend for old school arcade fans.