This is a question not an assertion. I wonder if the type of play that happens with experienced players, especially DMs as players, is goofier and more about the impression it leaves on each other than it was back in the day when we were learning the game.
Granted, meta-goofiness has always been there in my experience. Even the most dire of dungeon situations could be put on hold for joking around.
Also, with adult players brand new to the game I've seen a goofiness-used-as-defence appear. Where they aren't really sure what to make of this game and so pick funny names for their character and ask about doing silly things. They don't really understand the boundaries of the world or what their choices are and they don't want to look foolish in front of their friends.
But aside from that there has always been a kind serious desire to survive, desire to explore and find what is behind the next heavy oaken door.
The type of play I'm talking about is related to carousing tables. It is a kind of play that says "I want to put my character in a pickle because that will be funny. I will make choices I know to be bad for my character because that will make things interesting." The character that drinks from every pool in a world that has magical pools. The player that releases the demon from the iron bottle when they know it is a demon in the bottle.
I'm wondering if this comes about because the games being played are more one-offs (although Flailsnails allows people on G+ to use the same character again and again) so there is less concern for keeping your character alive to see the next session and also a sense of "We need to pack as much fun into these hours as possible. I may never see these guys again"
I'm wondering if it has to do with playing with folks you don't know as well personally and so the meta-joking is harder. When playing with people you've only known as a name on the internet maybe the easiest joking to do is within the game.
Maybe it is just a matter of jadedness; more experienced players have already survived the hardest dungeons, have achieved name level, have run their own domain. There is little fun left in to trying and eke those earning out yet again.
As I type this I'm also wondering if this is related to one of the trickiest parts of our game; how it tells you to survive on one hand and calls you a coward if you don't try to open doors or chests. It is the whole courage versus caution problem- why even go into this dread place if we know a vampire is there. A kind of nonchalance seems to be a very sophisticated way to handle this problem by sidestepping it and placing on the character's shoulders: "Of course we might die, but Rutherford of the Top Hat is too dumb to realize it."
Of course this is all assuming that what I'm asking about is actually a phenomenon. And there seems to have always been a thread of pretty cornball things going on in the game since the beginning (I'm thinking now of Arneson's turnstile in front of his dungeon). Maybe I personally like a more serious take on things, want to survive, want to climb in level and am just seeing a different style of play.
I don't know. How serious do you take your play? How does that change depending on context? What is the limit of too serious or too goofy for you?