Thanks for the prompt reply, I'm going to add one last thing to this discussion:

"I should caveat this with the fact that I would probably struggle to recognise our more deeply held shared meanings, in the whole fish-recognising-water sense."

Aha, this is where I think human language limits us, since it's our secondary nature to make assumptions and pre-judgements (to keep conversations going) that fit in neatly with mass-accepted beliefs or "Schelling points," as you referenced. Making too many assumptions can hurt deeper connection, I fear, because stereotypes—although holding some level of truth—hold condensed representations that dehumanise and treat labels like caricatures. Think, for example, of any modern or old identity label: gay, polyamorous, conservative, female, etc. As their meanings drift through time, so will their collective connotations held by different groups of people, because every single word I mentioned has had unique meanings and 'caricatures' in the past and will continue to evolve in meaning. In linguistics, I think this is called semantic drift—such as semantic weakening and bleaching—though take my words with a grain of salt. I'm no linguistics grad (at least not yet ;) ).

I do wonder how the future is going to progress, because I fear we will eventually return to our primitive, cave-like bubbles, and society will eventually fracture into many smaller ones. Perhaps I'm too much of a cynic, but this "shallow" shared meaning, as you said, will break down. Because let's face it—how long do collective shared ideas stay locked in place and last? They usually break down, and I do think, with the modern day and age, the only two possibilities that I see are either a return to or a rise in one united dogmatic institution (example: the Catholic Church) or the complete opposite—anarchy—because "neighbours in possession of wildly different world models" is terrible politically for the health and progress of society, in my opinion.

Other than that, much thanks for your response, and I do agree with you—it all boils down to us interacting with more people with different mindsets and beliefs today (tolerance and liberalism can take their credits here). But overall, I do think the specialisation of information will have an effect on society as a whole, especially with the rise of AI, which is more likely to give personalised and uniquely catered responses to an individual based on what they want to see and hear (preach to the choir, essentially). I mean, just look at the new Grok update—it's literally shelling out Musk's pseudoscience :(

All in all, the real question is whether this model of understanding sticks with us because it helps us deal with the barrage or "firehose" of information daily by personalising it, or if it tears us apart more and creates further divisions in society till it tears apart due to a lack of common ground and shared understandings.

Hazel.

"we live in the same world and interact all the time, we will share a lot of meanings, and this will make them look somewhat objective" 

Ironically enough, although this may not have been your intended meaning but what crossed my mind was whether our culture is creating a further divergence between the meaning people assign to words/phrases or further amalgamating and uniting them, particularly in regards to social media and the internet. 

On one hand as more people are exposed to the same media which is on par with globalisation and our current monoculture, Wouldn't it make logical sense more people will recognise these meanings and references en masse? Take for example a song, I don't know maybe "Gamnam style." with 5.6 billion views you'd think most people would associate these words within the song to the same cultural zeitgeist, no? However, as you said "The ocean, in this analogy, is [people's own unique] world model"

I do think here all 5 billion people may have assigned their own personal meaning to the song. Some may have listened to it to grieve a family member, some may have listened to it with their family, others may not even have close family and simply listened to it with friends, and the list goes on with interpretations.

Now the question lingering here is - even if we don't take into account social media echo chambers and confirmation bias- Is it impossible to ever reach a similar shaped iceberg among a group of people, EVER? Is it doable or does personal experience dabble into this and obfuscate meanings assigned to words even further? 

And how does globalisation and so called "mass" media play a part? or is its effects dulled by echo chambers and the specialisation of pop culture today to the point where (I'd argue) Pop culture was never "Pop" at all cause everyone assigned different meanings to what they experience?

Ironically enough, even here I have perfectly demonstrated the use of the theory you mentioned as my use of broad terms like "globalisation" and "monoculture" might carry pejoratives and negative connotations to specific groups of people with certain political stances. I do certainly hope you get what i mean though. ;) It seems more like a paradox to explain. Oh well, I guess all we can do is try.

Would love to hear your thoughts on this,

Hazel.