Content is abundant. Thanks to the internet which has created an economy of abundance. Curating content is becoming a prominent niche in the creator economy. The realization that most people don't have time. And curating is an easy, low barrier to entry way to save time for other people, i.e. your audience. Saving time for others is a form of value that you can exchange. You don't even have to be an expert in a field to curate. Spending some time on related websites and forums can help you identify what is part of the trend. Stumbling upon content that is "interesting" becomes more easy that way. The tricky part is to identify if that meets the minimum-value-proposition, whether it is engaging and whether it should be curated or not.
Getting it out to the world has never been easier. A lot of platforms exist that could help you kickstart a newsletter. Platforms like Curated are focused on curation as it's main form of content for newsletters.
Saving pieces of content and capturing information and data is almost free thanks to technology. Hoarding information in the form of bookmark managers that are not tended to and overflowing to do lists are more common. Simply because we are exposed to more content than we have time for. In such a world, our attention becomes the new currency for social transactions (liking a post, sharing a tweet etc.) on the web.