Not on that site, perhaps not, but other plane related sites have always had that information available. It's not unique or new. It doesn't mean the banks "own" Delta or Frontier. It means that WF leases to them.

AWAS or Ansett was the largest leasing company until it was folded into Dubai Aerospace. You could easily look at the sky and see 60% of planes up where Ansett owned. Most sites are just going to give ICAO/Airline.

It certainly is posted on other sites though, simple TN searches always pull up registered owners.