> would it necessarily mean the other stocks they might've bought (i.e. the rest of the market) will not get the cash infusion and will thus likely drop in valuation?

¯\_(ツ)_/¯.

Almost certainly, to some degree. But that doesn’t mean anything has to drop. Just not rise, or not rise as much as it would have. Or potentially some other company that would have gone public or sold shares doesn’t do it now.