Rifle Scopes Iron Brigade one Piece Base and Rings

I saw those. I see it still mounts on a rail. Do all mounts now require a rail attachment?

No but as mentioned with a one piece ring and base set up it limits your ability to adjust the scope for eye relief. You can only push it so far back or forward. I had one on a rifle years ago and got rid of it for just that reason. It worked fine mechanically but not something I would recommend for the reasons above.