The RTX 2070 is based on a 445 mm² chip;
Vega 64 is based on a 495 mm² chip;
Radeon VII is based on a 331 mm² chip and has 16 GB of HBM2, making it much more expensive on that count;
Meanwhile, the RX 5700 is supposed to be around 275mm² (see estimate from pictures of the chip here
There is the potential that AMD prices this card very competitively. This chip is most probably smaller than Nvidia's TU116, which powers the GTX 1660 Ti, which comes in at 284 mm².
If they price it like the 1660 Ti ($279 base price), but with ~RTX 2070 ($499 base price) performance, that's very good progress and Nvidia will be in a tough spot. Better help the devs crank out some more RTX enabled games to justify the price (or come out with 7nm cards already).
It would be a good move if they priced it like the GTX 970 ($329) to remind Nvidia how cards used to be priced at in other times.