PowerShell - SharePoint - How to get SPO site created date

You can get SPO site collection date by using below PowerShell script

Get-SPSite -Limit All | %{$root = $_.rootweb; $date = $root.created.toShortDateString(); 

Write-Host "$($root.url) was created on $($date)"}  

Fuente: https://www.c-sharpcorner.com/forums/how-to-get-spo-site-created-date