There is a growing sentiment that the US shouldn't be relied upon for the technologies that many people and businesses use every day. These privacy-centric recommendations come from a variety of European-based companies and organizations, that you should definitely consider checking out!
What I always miss in these lists is an alternative to Slack, which I also think would be one of the most important to get right since:
I have looked into Whaller, but would still prefer an EU-made open-source version of something like Mattermost.