These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Fridge Brilliance: Zero expresses worry at having to deal with R.L. Yoshi and John in the second round of Minecraft: The Walls. In the first round, Yoshi killed two people on his own and Zero doesn't know much about John, so it makes sense he'd consider them both as difficult foes...even if they are definitely not.
Frank also says he's more worried about dealing with Yoshi than Fury in the third round. Yoshi killed Frank in the first round even though they were both equally equipped, but Yoshi was weak from dealing with John.
Another example from The Walls is Zero instantly being able to tell that Yoshi was the one who built the other team's sniper tower in round three just because it was made out of wood. One would think this is just because Zero knows Yoshi's dumb enough to try that, but if you watch the entire series from Yoshi's perspective you'll see that he always starts off by gathering wood, and doesn't do much mining. So Zero would know that Yoshi would have lots of wood lying around.
A non-Walls example is the Oracle of Seasons / Ages Dual LP; Zero plays Seasons, which is more adventure and combat-based, while Xeno plays Ages, which is more puzzle-based. Back in Super Mario Bros., Zero stated he was normally the kind of guy who liked to go Leeroy Jenkins, and solving puzzles would keep him from doing that, so of course he'd pick Seasons.
Zero likes playing Mario romhacks? Well, one of his names is UltHaxor...