Good price, seems like Rad has too many bikes in stock and needs to lower their inventory, or are their ebike sales down, or ebikes in general sales down. Maybe it's just the Black Friday time of the year, they may just want higher sales records as companies want these figures to project future sales, etc. and be able to show their ranking in this field.
Personally, I'm really not too sure how much more they could do to the Rad City for 2020. I think the big jump was the 2018 to 2019, and any changes might be minor. Maybe an update to the display screen with a clock in it? Improvements in the seat? What ever it is, I'm not sure there is much that would make me regret my '19 purchase. My brother in law and I pitched and made one order with two bikes and got the $100 per bike discount back in August. He put over 1,000 miles on this from August til it got cold here in late October.
With the tariffs either in place or coming in the future, the margin for profit is probably not as much as you think. And with the current price cuts, that margin must be fairly thin.
I am guessing that although they make some money off the bikes, the accessories are what they actually want to sell - recurring use items. Over the lifetime of rad-ownership, they probably expect to make more profit off those.
And all the word-of-mouth helps them sell slightly profitable eBikes in the meantime.