Some things move easily to DVD.
Eugene Onegin with Renée Fleming and Dmitri Hvorostovsky appeared very quickly on the Decca label because both artists as well as Valery Gergiev are contracted to Decca.
I Puritani is released on the Deutsche Grammophon label because Anna Netrebko is contracted there. She and Villazon and Elīna Garanča perform so often together in part because all three are contracted to DG.
Bryn Terfel and Anne Sophie von Otter seem to appear on both lists.
Angela Gheorghiu and Roberto Alagna are both Decca. But Alagna and Netrebko are on different labels, making a DVD for Romeo and Juliet doubtful.
Joyce DiDonato is EMI while Juan Diego Flórez is Decca. This may prevent a DVD of last season's Barber.
We all wonder why a DVD has never been made of the wonderful Rosenkavalier with Kiri and Luciano who both record for Decca.
And what about the Nozze di Figaro with Bartoli, Terfel, Fleming, et.al.? Why don't we get that?