Forum Discussion
Introducing Workspaces in Edge | New feature
If you'd like to play with the feature, you could try creating new browser profiles... perhaps by installing Edge in a VM.
(I believe that someone previously stated that the user assignment for these 'controlled-roll-out' features gets chosen at random during/after installation?)
I don't suspect that Microsoft has forgotten about this; rather, the team is likely holding it back* until they are more confident in the final form in which it will appear. Let's give them time (yes, perhaps even another year or more) to do user studies and get it right the first time.
Perhaps counter-intuitively: the longer it takes to be released, the more likely it will be retained as a long-term feature.
* If I were the project manager (and I'm most definately not), I wouldn't let this sort of thing get released until a) it was much more tested and polished and b) all of the other Edge fires were put out. (We're still in the midst of a pandemic, after all.)
Update 2022-01-12 (since the reply / quick reply buttons are disabled for me right now, for a reason that I can't extract from DevTools):
In Edge 96 or earlier, if one had launched Edge with the appropriate command-line flags and then later launched Edge using the normal icon, any workspace windows the user had created just appeared as normal windows.
If Edge was closed and re-opened with the correct command-line flags, the workspace windows that were previous closed would appear and be classified by the correct workspace name/color.
After the v97 update, this behavior changed, and any workspace windows that weren't actually open prior to the update appear to have been lost!
These windows may return after downgrading to Edge 96... but in the meantime: if anyone has been using Workspaces and has not yet updated to v97, make sure you back up those windows before the update occurs on your PC.