It just enables a feature that changes the links in your notifications to automatically log you into your WA account when you click on them vs having to login after clicking on them. This assumes you logged out and your credentials aren’t cached in your browser.

Turn it on. I click on the links in my emails and I'm automatically taken to the WA page and automatically logged in when I get there.

Put it on so that you can get e-mail notifications and see what you get. Later on you can decide if it is worth it or not.