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Why does Arm still support short descriptors?

What I'm asking is ARM Architecture Reference Manual for ARMv8-A  says in AArch32 there are two translation table formats:

  • Short descriptors: 32 bit
  • Long descriptors: 64 bit

On page G4-4726 (Issue B.b), there are various points listed that each table descriptor provides. I'm looking at them, and understand that the long descriptor can do almost everything what short descriptor does. The thing I could not understand is why they did not depreciate the short descriptor as the Long descriptor could be used to the job of the short descriptor?

Is there some simple usage/advantage of the short descriptor over the long descriptor that I'm missing?