Yes, that seems to be broken at the moment, but from a tax law standpoint I'm not convinced that a 179 c/o from prior to 2018 would be considered an item of QBI.  Check the regs, I know they're pretty clear when it comes to PAL carryovers and the need to track pre-TCJA and post-TCJA amounts when determining QBI.  I'm assuming the same concepts apply to S179 pre- and post- amounts.

I'm not saying I know the answer, just that you might want to research it more before reaching your conclusion.

Rick