What drives a poor reputation for the Rogue class?

[Skrum]

"super deadly encounter". It's so super deadly, that they beat all of them, don't have to rest because those get interrupted, and still don't run out of resources. That's how deadly the game is!

The Gauntlet is precisely what clued me in to how optimizer DMs and optimizer players just vibe and make the game work to the players' favor.

On this point, my guess is Ludic is talking about "deadly" as in what the DMG would call a deadly encounter (like in terms of CR). The qualities I would ascribe to such an encounter are, if not handled correctly by expending notable resources to contain and/or end quickly, will spiral out of the players' control, or end up in a grinding battle of attrition that leaves some characters at very low hit points. This is exactly where the rogue, with their lack of burst options or situational resources, can falter.

Does "Deadly" mean the characters face risk of death? Well, yes and no. 5e makes it really hard to kill characters, and for them to stay dead. A deadly or deadly+ ranked encounter IME does not follow the linguistic meaning of deadly; rather it's just a CR-based ranking. Usually, the implication is that poor decision making or poor optimization could lead to the characters losing or dying.

For experienced players playing optimized characters (that have notable access to magic items), deadly+ is kinda the only encounter worth running. A medium or hard ranked encounter is just...not really worth rolling initiative for. That is, unless there's time to run several of them and the whole table enjoys that kind of grindy, slow drain of resources (time and a place, IMO). But personally, since RL time is often at a premium, I prefer to narrate or use skill checks to resolve lessor encounters and only enter initiative for the so-called deadly+ battles.

Heck, I main Bowser in Smash.

Pfft Bowser is midtier at worst. Zelda and King Dedede, now we're cooking with gas. #lowtiersriseup #jethammeristhebestmoveinthegame