I think we can all do with a little less cynicism at this point and simply realize that it's probably because games are built in with more flexible difficulty these days. Never mind that story-driven games would find it counter-productive to halt your progress, so the rare instance where something is 'too hard', there's other checks in place e.g quicksaves, grind-friendly zones in RPGS, adjustable difficulty during the campaign, etc.
The games that ARE too hard (ala SMB, I wanna be that guy) are designed for people seeking out that difficulty in the first place. In games where that level of difficulty wasn't intended, a sudden spike can be perceived as an imbalance by the people playing it, a flaw even. Human Revolution's bosses are a perfect example of this.
Cheatcodes were a necessity in a time where game designers simply didn't have all these tools available to them (as well as the benefit of hindsight). Could also be that there's a lot more work being put into games now and since they're not the 4 hour timesinks of days long gone past, cheat codes cheapen the experience. Or even break the experience, since games are built with a lot of restrictions in place, and having something like the ability to walk through walls damage your game severely.
What other cheats are there even that could be necessary in this day and age? Unlimited lives have been done away by quicksaves and checkpoints, level skips are sometimes built into games where chapters are a thing, and something like god mode feels laughable in anything that's not a serious sam game.
It's not all gloomy and corporate-controlled conspiratorial nonsense everyone. Achievements can easily be bypassed through other people's save files and steam IS playable offline.
I'm just saying it's possible we don't need cheatcodes.
Edit: As for potential hilariousness factors, there are MANY sandbox PC games that come with a developer console. GTA 4, Fallout: NV and Skyrim are all great examples of games where you can still enable 'cheats' for the lulz.
