Back when I did TA tech teaching there were many, many student movie projects saved due to target disk mode. Too bad that FireWire is depreciated in favor of USB.
I'm no English major by any stretch, they never teached us grammar at school ;0)
My take: Deprecated is also used in computing to refer to the current status of a particular service or part (e.g. of a program or OS). "Parallel port printing is deprecated" means "Parallel port printing is 'no longer going to be supported going forward and likely to be removed completely'". Strictly yes it was deprecated as a completed action in the past but the status is that it is deprecated now.