When that social contract disconnect happens, both the player & the GM enter a discussion absolutely certain that they have the social contract and the system supporting them except the GM no longer has mechanics pressuring against the player's misalignment. Previously those mechanics would encourage other players to proactively speak up out of self interest for their PC before the GM : Player discussion might be needed & there is no longer a quick page or less clearing things up because it's been replaced by a pea soup of fog about storytelling friendship tradition & camaraderie that either kinda sorta supports the player's misinterpretation or says nothing of particular use beyond vague feel-good vibes.
I think we are pretending if we take the position that the behaviors we are talking about weren't already well-established early in the game's history. They get expressed slightly differently from ruleset to ruleset, but the underlying impulses are much the same.
Actually no need to pretend anything of the sort. We can point to why the landscape has changed in ways that make those clarifications even more important today than they were in past editions. I linked to a different part of the video on that 44 rules ragequit GM from a couple years ago that highlighted it earlier in this tangent.
Professordm:" the players clearly believe that what is written in the books and what Matt Mercer and and people do on the internet are the authority of dungeon dragons they don't accept the idea that the game master is the ultimate Authority". Critical roll could not have existed at any point before fairly recent in computer history, the tech simply was not there even when we were spending multiple minutes if not an hour+ downloading badgerbadgerbadger strongbad & similar quicktime files decades ago in the pre world of warcraft world & there was a whole edition that tried to compete with that before 5e came along.
Even beyond the asteroid sized impact that critical roll & online video games had on how nerd gaming culture has evolved since "early in the game's history," The history of that 44 rules post PDM was talking about there shows why it's even more important for d&d to be clear about it than it was then.
That 44 rules was obviously the last straw for a burned out GM & the linked/quoted dungeoncraft video goes into good detail on why it's safe to assume such a thing. Relevant to the PHB omission in question though is the fact that the internet's reaction to that 44 rule post was immediately trashed the GM in question, I'll quote bob worldbuilder's description of that reaction though to avoid judgement about my rose colored glasses & similar
A couple weeks ago everyone on Reddit, and then on Twitter, all lost their minds over one angry game master’s “44 rules for dnd.” Just burying this guy, ‘haha what a horrible game master.’
Back in the old editions the kneejerk reaction to a GM : player disagreement was pretty much to defer to the GM if possible & obviously the internet wasn't really in the picture as anything recognizable. Today that needle swung so far in the other direction though where any sorta "
wait is it possible the players of this 44 rules GM are awful teenagers?" was completely drowned by the urge to bury the guy while merely noting in post 666 the impact of losing a mechanical incentive that made other players push back if another player tries to drag the game in a seemingly unproductive lets be pirates direction led to a post explaining how the GM could "easily" make it work. When it was clarified out that the ease of doing so had nothing to do with the point there was a
third tangent spawned about how they had never seen someone complain because they couldn't be pirates
on the same night. Then the most players are reasonable tangent grew legs & evolved. The default assumption to a GM : Player disagreement is now that the GM is
a combination of reference book epic Storyteller event coordinator and life coach who should be doing everything they can to delight the players per both PHB & DMG.