Are you joking? It provides no specific action they're taking to prevent this type of thing in the future, and it's internally inconsistent (who are "the people whose accounts we intended to disable" who they "will not deactivate their account and they will be able to access Slack when they return to countries or regions for which no blocking is required"?).

I've spent the day messaging and talking with friends who work within Slack in an engineering capacity who feel, frankly, betrayed by the organization. Slack advertises itself internally as an engineering-driven company and on the security side, has an incredibly elaborate system of internal controls that I have espoused emulations of during my consulting that, and I am being very specific without being too specific here, were bypassed to perform these account bans. Slack's security team was bypassed. Slack's internal controls were contravened. Slack has demonstrated that they can access every location you've ever logged in from and will cheerfully give that information up for the pleasure of the US Government without it even being required of them.