I actually find this to be a really interesting question. Founders do have significant sway in these kind of deals, in terms of advocating (or not advocating) for employees.
How are Slack employees doing financially?
The direct listing was good to most everyone I know (lots of former Twitterati at Slack), and this deal doesn’t seem to have changed that situation.
The post-acquisition exodus has started, which might imply folks aren’t interested in joining The Machine regardless of the money.