With the newer versions of Outlook 365, when creating a new invitation, a Teams Call link is automatically added to every meeting, which might not be wanted by some customers. Here is a quick way to disable it for the whole tenant:

Connect-ExchangeOnline

Set-OrganizationConfig -OnlineMeetingsByDefaultEnabled $false

To check out if the settings has changed:

Get-OrganizationConfig | select OnlineMeetingsByDefaultEnabled