The biggest issue with switching is your "must have" applications.
A lot of people spend time trying to make them work, it often doesn't work well and so they go back.
Take Sync, Linux has similar solutions (insync is a popular one), but there alternative solutions. Perhaps the server could run syncthing or your tooling supports ftp, etc..
The key thing is not to ask for the equivalent of X, but think what you actually use X for.
So if you use Sync to share video on Slack, you don't need a Sync replacement you need a way to share video on slack.
Alas I think Photoshop is the one killer application