Afraid it's part of a worldwide trend among politicians, who see museums as ballast, a cost item and a producer of nothing useful, a tradition at best. By itself, that fits into a political rightward shift as the Soviet Union ceased to exist. You would have thought that the unemployment of the crises of 1999 and 2008 would have caused a balancing out... The politicians are supported by civil servants who see museums as playgrounds for school children, whose school funds will cough up the money to pay the bills. Try seeing the superb numismatic collection of the Smithsonian, for instance.
In my (limited to one occasion) experience, sponsors are not involved with the scientific level of an exhibition they sponsor. Rather, they worry about the "message" of the exhibition and how it fits into the corporate image the marketeers think they have created. Citi was involved in some bruising court cases, following the Lehman crisis. It came out smelling foul and looking unresponsive, secretive and ingrown. I suppose their sponsorship is meant to convey a message like "we love money", but also "we contribute to the community". Ironic, that banks seem more attuned to community than politicians.
With the negativism about museums going on, I wonder if we are not going to see a shift to the internet. I remember the days when the BM had case after case of British coins, laying out the numismatic history of the country in strict chronological order. It wouldn't do today, the schoolchildren would hate it, but Stockholm still has such an exhibition and I spent hours ogling it. If there's a public for it, why not a virtual gallery? Let the kids gallop among electronic games and let the old fogeys do the surfing...
Peter
