A purchaser could buy ILFC to run out the current leases on the aircraft in order to collect all the rents that are due to them. If that number over the long term is higher than the purchase price, then it makes sense, and developes a return on investment.
The same company that would do that would almost certainly be unable to raise the huge chunks of cash that would be required to fund the next round of purchases, as ILFC had a sweetheart deal with the insurance end of AIG as a place for the insurance companies to park their billions during good times. These are no longer good times.
Any new company that can't raise money as cheaply (and ILFC did it almost for free) will look long and hard at upcoming purchases and maybe cancel a lot of them.
Cheers
Wino