Agree. There must be significant differences in strains. Seattle's weather isn't that sunny, at times, and Washington state, despite being the location of the first deaths, isn't having the problem NYC is having.
If you look at it from a biological warfare angle, it begins to make sense tho. NYC is a prime target city - the most deadly strains would be deployed there, along with deployments at other strategic cities, military installations (which are being kept out of the news), naval installations and ports-o-call, etc.
Less deadlier strains could serve to inoculate an attackers own population as well as create a smoke screen that hides such an attack and deployment of more lethal strains in strategic locations like those I've listed above.
It can all be explained away by natural mutations of the virus of course - leaving an enemy blameless, especially if the country it planned to attack had helped fund the research for development of such a virus as happened in this case.
Then their are those who would be inclined to take advantage of the situation, Islamic terrorists come to mind, by becoming super-spreading martyrs for Allah. And let's not rule out those who think there are too many people living on planet earth now. Some have known connections with the very scientists suspected of creating this novel corona virus.
I keep thinking that this is as close to a perfect weapon for taking down a country like America, as can be imagined. We have many powerful countries and people with the means to pull something like this off, who want to see America fall, each with their own reasons.
The Chinese were not planning on Trump shutting down travel from China. That would have hit the West coast with a second larger wave. With the more deadly strain. The Chinese deployed every trick and every spy and every bot and every paid for stooge to stop Trump from doing that. Wonder what the flu bros position was back then ? We can guess, I guess. Lol.