Ultraportable PCs are usually more expensive than "regular" sized laptops of the same specs, because it's difficult to cram the same hardware into a smaller case. If you look at ultraportable computers of yore like the Toshiba Libretto or Sony Vaio, they were much more expensive than their larger kin, because it's a niche market, and because components are more expensive at that size.
Look at the GPD Pocket, it's $500 with roughly the same specs as the GPD Win. It's doing rather well. You can get a much better laptop for that price but there's obviously a market for ultraportable Windows machines.
The GPD Win 2 will have significantly upgraded specs, so if it ends up costing $500 that's not that bad. Yes, you could get better hardware for that money but there's a lot to be said about the size.