No it's not the same as your grandma. The point is that it's now more expensive to find the correct information to learn from. You don't know it's an LLM ahead of time, and you may spend hours until you figure out something is off. Hence why reputable sources will become more valuable.
> If you develop the skill of judging information by its merit rather than source..
Did you read example #1? I'm not talking about some piece of code from an LLM that you can verify or some political opinion that you can take with a grain of salt, but information that you can only gain and/or judge through expertise:
If you're not a physicist yourself, you can't judge "information by its merit" on specific physics topics, because you don't have a solid baseline.
Similarly, in growing plants, each plant has its own peculiarities, and only people experienced in growing it can tell you anything useful - it's knowledge accumulated by trial and error. Not knowledge that your "great discerning mind" can assess on its own. Even a botanist can't tell you the ideal growing conditions of a plant that they've never studied before.
What if your physics book is wrong because knowledge has advanced since it was released - you can still find lots of publications and people with degrees blissfully unaware of Hawking Radiation. What if your botanical book is wrong because facts have changed since then - climate is changing and so does flora. What if your book is wrong because it's state-funded propaganda mixed with petty fights of a bunch of people with suits and strong opinions disguised as academia - a huge chunk of linguistics is dealing with exactly this issue.
Again, you seem to miss the point that the idea of questioning new information, which was already useful to navigate life before LLMs, before television, before newspaper, before print, before clay tablets, even before speech itself, is equally applicable to LLMs as to any other form of communication. You just need to upgrade your strategies a little and that's it. Don't blow this out of proportion "somebody gasp lied to me on the internet!".