To disable for individual users:
Set-clutter -identity [email protected] -Enable $false
For an entire organization (tenant)
Get-Mailbox | Set-Clutter -Enable $false
You do have to be signed into your O365 environment by PowerShell:$session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri "https://outlook.office365.com/powershell-liveid/" -Credential $cred -Authentication Basic -AllowRedirection
It will ask you to authenticate. Use your normal creds.
You will see another module load and you're in to run the above scripts.