PowerShell: Conditional CSV cell value

Yes, using a switch statement is an option.

You can combine it with Select-Object and a calculated property:

$oneWeekAgo = (Get-Date).Date.AddDays(-7)
$twoWeeksAgo = (Get-Date).Date.AddDays(-14)

$csv | Select-Object Enrolled, @{ 
         Name = 'Status'
         Expression = {
          switch ([datetime] $_.Enrolled) {
            { $_ -lt $twoWeeksAgo } { 'DISABLED STILL PAST DUE'; break }
            { $_ -lt $oneWeekAgo }  { 'DISABLE'; break }
            default                 { 'PAST DUE' }
          } 
         }
       }

The above outputs the resulting objects to the display, showing (just) the Enrolled and Status columns in tabular form, as in your question.

In order to update the original CSV file while only updating the Status column and leaving all others intact, use the following:

• To be safe, back up file.csv first.
• Note the enclosure of the Import-Csv call in (...), which ensures that it is read in full, up front, which enables updating the same file in the same pipeline; if the file is too large to fit into memory, remove the (...), output to a temporary file, then replace the original file with the temporary one.
• You may have to add an -Encoding argument to the Export-Csv call, because the latter's default encoding is otherwise applied, which is ASCII(!) in Windows PowerShell, and, more sensibly, BOM-less UTF-8 in PowerShell (Core) 7+.

$oneWeekAgo = (Get-Date).Date.AddDays(-7)
$twoWeeksAgo = (Get-Date).Date.AddDays(-14)

(Import-Csv file.csv) | ForEach-Object {

  # Update the .Status property.
  $_.Status = switch ([datetime] $_.Enrolled) {
            { $_ -lt $twoWeeksAgo } { 'DISABLED STILL PAST DUE'; break }
            { $_ -lt $oneWeekAgo }  { 'DISABLE'; break }
            default                 { 'PAST DUE' }
          } 

  # Output the modified object.
  $_

} | Export-Csv -NoTypeInformation file.csv