Personally, as a favorite major source, I’ve been reading and keeping up with the IndieWeb community (indieweb.org, their wiki, newsletter, and chat) since about 2014. Their community, while relatively small, is large and diverse enough that I’ve seen and been exposed to a variety of technologies, online movements, and even social movements in the last several years that I’m sure I would have never seen in the mainstream until after the sea changes had already occurred. Without an insignificant amount of attention they also manage to do it all with a flourish of kindness and care.
The secondary issue isn’t just seeing or hearing about it, but also having the bandwidth to delve into it, explore it, make sense of it, or even do something about it. I might posit that IndieWeb is working on something even more powerful and subtle than the Fediverse idea, but that it’s not quite ready for mass consumption (yet).
If I had to choose a single source to optimize for time and attention across a variety of sources and topics, I might recommend following Kevin Marks (also at @KevinMarks) who consistently sees and finds some of the best in technology that’s out there.
On the flip side, I’m sure that there are a variety of your own sources that you consume that may prefigure other changes and shifts. If you throw them over, it’s possible that you’ll missing seeing something else that may have otherwise been more obvious. Again, you have to adjust your time and attention to things which matter most to you.