I did trade-in for a new X. But after seeing improved range on MY, I changed my mind and ordered a MY instead. M3 and MY are priced right IMHO. NJ now has $5K tax credit for M3 and MY + no tax.
I feel there is a pretty good chance S/X will get interior updates along with bigger battery and 3 motors towards end of Q3 this year. And if CT price is any indication, price of S/X with bigger battery will be either same or less, not more. And when (not if) this happens, my car's (2018 MX 75D) value will take even bigger hit. And so I am trading in.