Just as you have to look at a text output of a unix command to figure out how to parse it and extract the subset of information you need from it, so do you have to look at the help metadata of a PS command to figure out how to extract the subset of information you need from its output.

The advantage of having objects instead of text is that if you thought you could parse the filename of grep matches by substring each line of `grep -H`'s output with `:`, you failed to account for filenames with colons. With PS's sls, its help metadata tells you it outputs `Microsoft.PowerShell.Commands.MatchInfo` objects, and the documentation for that type tells you it has a `Filename` property of type string.

One PS command is not "integrated" with another PS command; they're all integrated to .Net and a bunch of built-in PS types.