>It's not like PowerShell automatically adds support for sorting arbitrary data to an existing sort utility, either.
But it does. You can easily sort any data on any field even using your own custom comparator (try that with 'sort'!), using only one utility. Which had to be written, just as 'sort' utility in Unix.
>You could get the same effect by standardizing the labeled-groups-of-lines format output by 'aptitude show' and writing a sort utility specialized on that format (a 10-minute job in any major scripting language). Or you could just use one of the many portable interactive scripting language shells, like python or irb or scsh, which provide the same services for their respective bindings that PowerShell provides for .NET.
Well, of course you can achieve the same functionality as in PowerShell by replicating what PowerShell does (namely, by introducing structured data). The point is - no one is really doing it in the Unix world.