That is correct. If you have no data on the user you will still receive a message in regards to this. The reason why Roblox does this is because some people store data externally outside of Roblox on different DB’s then the data-stores Roblox so you could be a dev who does this and there is no way of checking really.
As long as you have no data in Roblox or outside of Roblox which relates to the user then you should be fine. If you have ANY data at all on the user, even outside of Roblox this must be removed as it is a legal requirement and you could get into legal trouble and account termination if caught.