You will soon be able to share Word for the web documents in Review mode, which limits recipients to adding comments or leaving tracked changes in the document.
When you share documents with Open in review mode only selected, recipients who open the document in Word for the web will be limited to adding comments or leaving tracked changes in the document. This can help prevent unintended edits to the document.

Image courtesy of Microsoft
People who open the document in the Word desktop app, instead of on the web, will only be able to view the document. They’ll see a notification to switch to Word for the web if they want to make changes.
With this feature, you can have more control over new edits, and only you (as the file owner) can accept or reject changes made by other people. If someone else leaves suggestions in the document, they’ll be able to reject their own changes but can’t accept or reject someone else’s changes.