This suggestion comes as an outcome of the discussion Is there any way to turn off automatic check for presence of Comment/Review fields in latest versions of Jabref?.
There are people who continue to use the «Review» field (for exactly what it says — reviewing, which is not exactly the same as commenting). While realising the decision to deprecate this field was done for a reason, I suggest the switch to be implemented that would make it possible to disable the said check (a check-box or toggle some where in preferences looks like a logical choice).
As the mentioned discussion shows, there is a simple workaround, so it is not some thing awfully important to be frank. But, the way I see it, it looks a bit weird (just personal opinion) to nix using the «Review» field label while allowing people to use fields with virtually any other name. After all, the word «Review» does have some thing to do with scientific papers ;-).