first, note that the virus appeared in these places at about the same time.
new york was unprepared, dithered on shutting down the economy and suffered a swift and vicious attack by the virus, which rendered large amounts of it's population sick very quickly and threatened to overwhelm the system, although i'm not sure the data backs up that actually happening. today, some areas in new york are reporting upwards of 70% infection rates.
california, on the other hand, was quick to act decisively in locking down the economy and initially featured less of an outbreak, although the reality of persistent community spread was in fact apparent the whole time. while no doubt in reality an order of magnitude greater than discovered through testing, infection rates in california would appear to have been kept relatively low.
over the last few weeks, however, new york has opened with few significant problems, while california has seen the number of cases skyrocket, to the point that california is now only about 40,000 cases behind new york, in total number of discovered cases. but, this is an inexact comparison. so, california has had to extend and reinforce a lockdown that ultimately failed to prevent the outbreak that new york got nailed with, by being hit off guard; new york seems to be in the clear, as far as anybody can see.
while it initially seemed like the death rate in california was much lower, there seems to be little reason to think, at this point, that california will, in the end, avoid a loss of life on the same scale as that suffered in new york. so, all of this extended hardship is unlikely to come with any net benefit attached to it.
today, it seems like new york certainly took the less painful path.
so, i want to draw your attention to the model that i posted here many weeks ago that criticized the "flattening the curve" model:
new york end up being red, california ended up being blue.
this isn't a prediction, it's a model. please realize that.
but, the argument is supposed to be that the same number of people will get the virus anyways, so you'd might as well slow it down. one of the key points i'm trying to get across here is that if you slow the virus down then you reduce the speed of immunity, thereby increasing transmission - and you actually get twice as many cases because it takes twice as long to get to herd immunity. that sounds like it doesn't make sense, but there's a difference between developing antibodies and getting sick.
you can tweak this. maybe it takes 1.5x as long. it's a model, it's not a prediction.
the other thing i'm doing here is arguing that you can't really flatten the curve, exactly, but can rather shift it. and, maybe that shift is valuable if it buys time for a vaccine. but, it's going to come with a slow increase in cases over time until immunity is reached.
don't get lost in this in nitpicking the numbers - it's a model, it's a conceptual thing, it's an idea. and, it's a valid critique.
unfortunately, it seems like much of canada (with the exception of quebec) also followed the blue curve.