I think it's just something that has to be considered in a wider context and people are bad at that in general.

See my friend who is quite obese and suffering from diabetes including kidney issues and bad liver enzymes, because he was obsessed with being big and lifting heavy things and obsessing about cramming as much 'protein' as he could thinking that weight lifting would burn off all the 'bad stuff'. He got way more protein than even any body builder could possibly need but was still always making a big show at gatherings of eating so much stuff to maintain his physique (which didn't look muscular, he always looked fat, but said his muscles weren't for show and that's why he looked fat not muscular).

So when some post seeks to help folks by indicating good sources of protein, it can trigger people that have no protein issues to make worse decisions, and it's worth pointing out that most people concerned about getting lots of protein almost certainly already have plenty of protein.

Well, if you're actively starving, then obviously you won't get enough. And if you're only eating e.g. rice, then you'd likely be satiated before you have enough of certain amino acids. But aside from that, it's quite difficult to not get enough protein, as carb-heavy food also contains protein.

I can recommend listening to this podcast/video for a more detailed explanation: https://zoe.com/learn/podcast-should-i-eat-more-protein