It's always been like that. The US sanctions are not new and many countries have equivalent. Established businesses simply block connections/signup/login from

It's always been like that. The US sanctions are not new and many countries have equivalent. Established businesses simply block connections/signup/login from sanctioned countries. It's part of the checklist for new apps. It's really basic. Slack is just another startup to discover that there are regulations to follow. They did very poorly on the interpretation though.