It seems the protagonist arc of metamodernism is more or less coming to terms with the fact we are on an absurd interactive ride, and we can enjoy it and that's enough.

Is this close to the mark?

Depends on the implementation and only just recently acquired the vocab, but I'd call that neutral form metamodernism

Strong form is "Acknowledgement of Absurd" + "All we can do is enjoy it"

Neutral form is "We can enjoy it and that's enough"

Weak form is "We can enjoy it"

/cameron for content experiments. I help Creators grow faster @ seemore.tv + /seemore. Posts at creator3x3.com.
Dev + Veteran + HBS. 
seemore.tv/cameron 🫡

If that is the case, then I don’t expect it to last long.

IMHO examination of sincerity is a bubble luxury. It's hard to explain how agents of power seem dense or even comical, but are so consequential. Their precursors acted no different but were less known; they were more mystical and less ironic.

Robespierre will return and metamodernism will seem quaint.

ooh interesting - what do you mean by that?