But that page is for "Kbin", not specifically "Kbin.social" which I note does not appear among the list of all Kbins already - https://kbin.fediverse.observer/list. So you don't have to wait for tomorrow - it's already too late to see its former traffic today.
Interesting: the Active Users Monthly (https://mbin.fediverse.observer/stats) for Mbin is 568, whereas that stat for Kbin was 2280. So even without including the extremely large Kbin.social (well... large in terms of total users, but obviously not active ones bc the service is down, which by definition precludes people being active on it:-), the suite of Kbin instances still seems to have ~4x more active users than the Mbin ones.
I would not have expected that, given the chatter about Mbin being exciting, and I wonder why - potentially historical precedence, if an older server simply has more traffic bc it was created first?
But obviously something more is going on with that data - i.e. & e.g. supermeter.social is reported to have the highest user count among the Kbins, but with only 736 total users, and if you add up all users from all 8 of those servers you get only about half of the 2280 "Active Users Monthly" figure - so I suspect that the activity for Kbin.social is being included in that after all? Otherwise something is very wrong with the extrapolation of "active users", to be more than twice the total ones (one possibility... past active ones vs. a smaller current total of people who deleted their accounts rather than merely abandoned them by walking away without going to the trouble of deletion).
Which would make sense - the website is reporting numbers accumulated over time, and even though Kbin.social is down now, it was not always thus, and it seems it cannot discriminate the history in terms of active users (Kbin.social vs. some other Kbin server I mean).
But that does complicate - possibly even invalidates - trying to compare the non-Kbin.social Kbins vs. the Mbins, in terms of active users.
So leaving active users aside then, I note that the largest Mbin has a ~6-fold higher total user count than the largest Mbin server. Also there are 8 total Kbin instances (aforementioned not including Kbin.social bc it does not appear on that list today), vs. 23 total Mbin instances. It's shaky, but it really does look like the Mbin instances seem healthier than the Kbin ones? (Again minus Kbin.social, which despite monthly active users seems by no means "healthy" to me?)
This ignores things like possible hyper-focusing on specific niche topics so a deeper look would involve how many communities are there, and perhaps traffic patterns like do people actually comment in those or is the server mostly just a base from which to access the Fediverse at large (which may not be a bad thing at all? just a bit different), etc.