Now that I read this thread through, it's time for me to make an actual not-joke post.
I wouldn't actually mind if they just kept the current engine for the Switch version going forward (provided that they fix the bugs), since I'd try to pick it up for half off anyway.
That's how I read their losses off the Switch version currently - make up for it by reusing the engine and as much of the assets as possible.
It's a shame that it didn't do too well, but that's what happens when you have a rather small install base coupled with mostly Nintendo fans that went out and bought the system. I still want to see the sales distribution for FIFA 18 in the long run, though. If that share of sales ticks up, then it may bode well for future entries to come along.