See other threads on this, but your statement here is made without any proof. Consider:
- 1 TB storage needs more RAM than the lesser storage for accessing the drive. Other's are mentioned I belive half a gb more than that other drives. Considering this Apple had no choice to put more RAM in the 1 TB offering, and you can't have 4.5 GB RAM
- Of the 6 GB RAM in the 1TB, there is no guarantee the user has access to all of it. For sure they'd only have access to 5.something because some of it being dedicated to interfacing with storage. What if the user accessible RAM isn't any more than the 4GB models? (I'm guessing it is, but the point is we don't know)
- What apps are you going to use that are going to take advantage of the extra RAM, even if it is there? If you are a huge raw video or photo editor you probably want the 1 TB storage.
- Most, if not all, apps written for iPads, even specifically the new iPad pros, are going to target 4GB of memory since you know, that is the market share
- Just like in "real" computers, once you have enough RAM for your usage, more RAM isn't going to help. Chances are great that 4GB of RAM is enough on an iPad, even an iPad pro of 2018.