To make it concrete: to move away from Microsoft (teams, sharepoint) and Google (drive), Nextcloud is a decent option, but you may also want decentralised group chat like matrix, maybe a better collaborative document server, à La Suite Docs, video conferencing like BBB or La Suite Visio. And of course a Single Sign On - one account to log on.
Altogether this is not something every individual person or collective may want to run for themselves, so you need a service provider, ideally a cooperative one, where you can be a member of and collectively maintain a production team and a process to evolve together - as technologies (and social needs) evolve.
In this sense the 
@coopcloud federation provides a backbone to work together on the development and maintenance of the tech stack as a "configuration commons". With the #dtf we became members, and it is exciting to see what is cooking there and how people/cooperatives collaborate along shared goals.
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