As for Oxbridge endowments catching up with the elite American unis . . . Eh.
From 2006 to 2014, Cambridge’s endowment grew from £4.1B to £5.98B.
In that same time frame, Harvard’s endowment grew from $28.92B to $35.88B.
MIT’s grew from $8.37B to $12.43B.
Northwestern’s grew from $5.14B to $9.78B.
UMich’s grew from $5.65B to $9.73B.
It looks to me like HYPSM are pulling away from Oxbridge while Northwestern and UMich (& UPenn and Columbia) went from being behind Cambridge to pulling even with or even ahead of Cambridge (depending on the exchange rate) and ahead of Oxford at £4.36B.
https://en.wikipedia.org/wiki/List_of_colleges_and_universities_in_the_United_States_by_endowment
https://en.wikipedia.org/wiki/List_of_UK_universities_by_endowment