So, amid all the feverish discussion over who is going to take NijiEN's spot as #2 EN agency, there have, in my opinion, been two aspects that have often been overlooked. One is data, and the other is... something else that I'll get to. Spoiler for those who want to get to the point: It's VShojo.
So I did the normal person thing and I went to all of VStats' monthly summaries, and gathered the numbers for total watch time, total hours streamed, and average CCV, going from September 2022 through to April 2024, covering 20 months in total (technically the Sep 2022 summary actually has the same data for August, but I didn't really take notice till later, so, oh well, I haven't got that row.) Using that data, I produced some charts. And let me note (because by this point, presumably you will have seen those charts) that I also was able to find similar data for VShojo, albeit covering the periods of the last 30/90/180/365 days from when I checked (11 May), so the data are both lower-resolution and a little offset.
Here are my own takeaways, summarised:
There had been a long downward trend for Hololive, Holostars, and Nijisanji EN, but this trend hit Holostars EN worse than the others earlier on, and Hololive EN has broadly recovered since Advent; it is the only one of the three whose CCV and watch hours in the first third of this year weren't worse than they were in the last third of 2022.
New debuts create a boost, but this doesn't always last: both XSoleil and Tempus VG built some extra hype during their debut month, but both metrics trended back down again afterward. Even Advent didn't create a sustained boost entirely on its own given that CCV dropped off again quite quickly; HoloEN seems to have done something around the end of last year to really consolidate. (Or maybe it's the botting, but IIRC that hasn't been frequent enough to massively increase the numbers, based on some calculations someone did last time I posted on this.)
Whatever the trends, both NijiEN and Phase-Connect are way behind Holo in basically every metric that counts. In CCV terms, HoloEN (Stars excluded) is bigger by nearly an order of magnitude at this point: on average HoloEN pulls in about 6500-8500 viewers per hour, while Niji has slipped below 1000 CCV for March and April, while Phase has approached that mark but still never cleared it.
It's interesting how Mysta's graduation correlates with a pretty big drop in NijiEN viewership, in a way that none of their other graduations seem to have done (although tbf Pomu's graduation and Selen's termination hit very close together).
Holostars EN was, in CCV terms, competing pretty closely with NijiEN until the end of 2022, and I have no idea what happened to make them lose ground so much faster during most of 2023.
The elephant in the room here is VShojo, which, as it turns out, has beaten NijiEN for 2nd place for as far back as data exist, and the comparison isn't even close. Even if you argue that Youtube and Twitch views aren't a 1:1 correspondence, they would have to be a 4:1 correspondence for NijiEN to be 2nd place ahead of VShojo at this point.
In short,
Actually, turns out maybe VShojo has been in the #2 spot the whole time, and
Everyone else still has a long way to catch up.