I mostly agree. Some nits, though:

> permanently less productive

A short-term reduction in profits reduces the discounted sum of future returns. Not as much as if interest rates were lower, though.

Also, the example of the virus could indicate that these infections are on average more common and more severe than we figured, and that could reduce expected long-term growth.

Finally, a "pause" on activity could delay productivity increases. Probably a small effect, but this could represent investment not happening in the short term.

I sent some lumpy buy orders yesterday, but I'm not sure I was right to.

This is the reason why more than a 10% drop or so (assuming this doesn't chain-cause a recession) isn't justified. That doesn't mean stock prices aren't permanently lower.