There are some small updates since I wrote:
https://ktnnsharepoint.wordpress.com/2019/08/01/share-copy-link-sharepoint-online/
I still recommend to change from ‘Anyone with the link’ to ‘ Specific people’ in the SharePoint Administration. Let’s see however the behaviour with the default settings.
SharePoint Administration
Policies > Sharing – Those are the default settings:
You can notice the new section ‘Choose the permission that’s selected by default for sharing links.’
Sharing per site collection is: Policies > External Sharing
Settings at creation
New Team
- New and existing guests
New SharePoint Team Site
- New and existing guests
New SharePoint Communication Site
- Only people in your organisation
File – With the setting above, this is what happens with a file
With ‘Share’
With ‘Copy link’
| SHAREPOINT ADMIN | ACTION | OWNER/MEMBER |
|---|---|---|
| Specific People | Share | People you specify can share |
| Specific People | Copy Link | People with existing access can use the link |
| Only people in your organization | Share | People in organization with the link can edit |
| Only people in your organization | Copy Link | People in organization with the link can edit |
| Anyone with the link | Share | People in organization with the link can edit |
| Anyone wiith the link | Copy Link | People in organization with the link can edit |
Ref. Utilisateurs externes dans SharePoint, OneDrive et Teams | KTNN SharePoint (wordpress.com)
Also not to be forgotten per site collection:
Teams Administration
Configuration Change in Guest access for Microsoft Teams (MC228482)
We’re making some changes to the default setting for Guests in Microsoft Teams
Beginning on February 8th, 2021, we are turning on Guest access in Microsoft Teams by default for any customers who have not configured this setting. This will bring Teams Guest capability into alignment with the rest of the suite, where the setting is already on by default.
What is the difference between external users and guest access in Teams?
Microsoft Teams Chat With External Users [NEW] Everything About Guest Access
External Users and Guest Access in Microsoft Teams: A Complete Guide (netwrix.com)
KTNN SharePoint 