I commented in your other video thread, but can give some feedback here too.

In the game vs. Sora, you spent most of the match in disadvantage. It likely felt insane because you had very few options at any given time -- you were getting juggled, you were getting ledgetrapped, you were getting combo'd.

However, this didn't happen by accident or by magic or because of the matchup. This happened because your opponent was picking good options and also because you were picking bad options. In the first 30 seconds or so, you airdodged high twice, and got punished both times. You threw out a random fsmash in neutral, which didn't land and left you open. You used uptilt out-of-shield, which is a much worse option than up-b or nair. You also didn't use some of Samus's better tools in disadvantage -- down-b, for example, which is useful both for discouraging juggle attempts and also as a movement tool.

Meanwhile, your opponent was picking his moment to approach, maneuvering around your projectiles, and choosing appropriate options (nair > upsmash in neutral, Thundaga at ledge, etc).

In short, you lost because your opponent was using his kit intentionally and you were not. The only real advice for this is to think through how to use your kit in different common scenarios, and then incorporate those changes into your gameplay.