The newsletter for reasons mentioned by orthocresol really is only useful, if you follow the site irregularly.
If you don't mind getting lots - and that might be a crazy amount, depending on the tag - then you can subscribe to newsletters for tags. That might be a great idea if you are a specialist in rare-earth-elements (8 questions in 2017 until now) and don't want to miss one of the rare (pun intended) occasions. It might be a medium good idea if you want to follow aromatic-compounds (265 questions in 2017 until now); it might be a terrible idea to follow organic-chemistry (2500+ excluding already deleted in 2017).
You can easily subscribe to a tag, going to the tag-page. If you hover over it, it opens a pop-up, were there are links to subscribe and for rss. (Theoretically that should work on any page, except in the favourite tag section.) You need to confirm the e-mail subscription.

Alternatively, you can create filters at https://stackexchange.com/filters and subscribe to these ones.

It is a bit tedious to get going, but depending on what you want to watch, it might be worth looking into.