looks like last time i posted this was 5/13/20, presumably from data i ran that day. phelan had season 141, now it has 150. naismith had 117, now it has 123.
in d1, it looks like worlds have either been stable or had small increases since then (probably mid single digit average increase per world? very roughly eyeballing)
in d2, there are clear increases - low double digits per world - perhaps around 20, maybe a bit more even. knight saw insane increases of almost double, from about 55 to about 100.
in d3, looks like about 6 months ago there was a temporary major spike for about 2 seasons - was that a free HD? it seems to have mostly worn off, but with some fairly clear lingering increases from where it used to be. perhaps around 15-20 per world on average.
all very roughly eyeballing it but it does look like HD has a significant COVID boost, or something. its not totally clear, in a way the lower d1 increases might suggest its new folks who haven't all made it up there yet. the faster d1 worlds did seem to be perhaps a tad more clearly up? but it may also just be folks picking up teams like d2/d3 better, who knows. perhaps because the d2/d3 worlds were so empty, they could better accommodate new coaches. IMO populations of 150-200 were fun, but too competitive for the casual fan - i think if we could wave a wand, it would be ideal if the number of d1 worlds was a bit higher than d2/d3 to get a more even spread on density. on the other hand, having less competition in d2/d3 seems ok, too. well i'll stop rambling but anyway, there's the data for whoever wants to look at it.