In /Posh-SSH.psm1, line 5 sets up $global:SshSessions as an arraylist.

In Remove-SshSession, lines 148 and 175 call $global:SshSessions.Remove($badsession). An arraylist, .Remove() has no return value, so that suggests Remove-SshSession is not intended to have any return value.

The C# code in PoshSSH/SshModHelper.cs, line 30 overrides the variable and makes it typed a generic list and generic list .Remove() returns bool.

Remove-SshSession returns a bool for whether the session was removed from a List<>. Unless the global variable can stay as an arraylist, then it doesn't. Either way, "list removal" is not related to the SSH session itself, so it seems like an unhelpful return value and is possibly unintentional.

It's documented as having nothing for "Output", but the example usage shows that it has.