I have that same question about filtering out a pool in Workspace.
We have tags set to filter within Horizon (Internal , External)
If external...the users see the icon (for an Internal only pool) , clicks on it, and it says that "you are not entitled to use the pool". They calls the Help Desk and say they are not entitled, and it leads to a lot of confusion.
It's been awhile, and this seems like it would be beneficial to others.
Anyone have an idea how to Exclude Pools in any Workspace version?