I think this video is missing the point of what it means for a game to be hard. Like, yeah, it's easy to win a round if you just play against someone who is worse than you. But some games require skills that are harder to learn, or require higher levels of those skills before you can engage with all of the game's complexity, so if your goal is not "beat this specific player" but is instead "master the game systems so that you can interact meaningfully with all of the game's depth" then obviously some games really are harder. Tic-tac-toe and Othello are both strategy games about placing pieces to control space on a grid, but you can learn to play tic-tac-toe optimally in less than five minutes, and even the best human players don't play Othello perfectly. It is not just about types of skills (although I would say that a game that requires you to practice more skills at once is harder), it's about how far ahead you need to plan, the number of possible decisions, etc.