Does PowerShell has something like "echo off" and "echo on" trigger?
You should use Write-Verbose instead of Write-Host, this will make your debugging data controlled by the variable $VerbosePreference. This variable has the same value set as $ErrorActionPreference, and the default is SilentlyContinue, which means that no verbose output is generated. You can set this to Continue and then have your verbose output visible.
I recommend you simply put
| Out-Null
at the end of any line where privacy matters... it's more or less the same as putting...
@
... at the beginning of any 'batch' line where you want output hidden from users.