Veritasium is legit, they cite their sources and explain concepts exceptionally well.
However, I don't think the conclusion of the video is "Democracy is mathematically impossible", but rather "perfect representation in a democracy" is mathematically impossible (but can still be much much better than FPTP).
The video basically goes through all the top voting systems and explains their pros and cons and the history of the mathematicians who invented the systems.
GoG's launcher can launch games from other launchers and it's really not a big deal to have multiple. It's not ideal to need a launcher but it's a snappy launcher and not at all the same terrible experience as Ubi and EA's that have the most obtrusive and sluggish setups.