Stock markets very rarely care about security, unless it's somehow front page news.

Investors would care if they thought Zoom’s customers cared enough to switch. I personally think this is terrible, but investors don’t seem to think Zoom’s customers care enough to change to a competitor, which makes me second guess whether or not this is actually a big deal to large customers.

my guess is this is of 0 importance to the stock market and large customers.

almost all video communications software works similarly to zoom, so that's that.

Tavis Ormandy joked about buying those dips because of this and I really don't think either of you are wrong and I might start doing it myself.

If a company’s stock drops after a major vulnerability, you should buy. Equifax exposed everyone’s financial data and their stock is back above their pre-breach price.